From 6ace46a024bd59073d34e11f7a4a3cd23ee1f793 Mon Sep 17 00:00:00 2001
From: PRATHAMESH CHOUGALE
 <106848418+Prathamesh-chougale-17@users.noreply.github.com>
Date: Tue, 31 Oct 2023 15:46:37 +0530
Subject: [PATCH 1/3] Important STL properties and function with example

---
 .../Important_stl_and_function_array.cpp      | 169 ++++++++
 .../Important_stl_and_function_string.cpp     | 192 +++++++++
 .../Important_stl_and_function_vector.cpp     | 389 ++++++++++++++++++
 .../important_function_of_sets.cpp            |  78 ++++
 4 files changed, 828 insertions(+)
 create mode 100644 Add Code Here/C++/Important_STL_properties/Important_stl_and_function_array.cpp
 create mode 100644 Add Code Here/C++/Important_STL_properties/Important_stl_and_function_string.cpp
 create mode 100644 Add Code Here/C++/Important_STL_properties/Important_stl_and_function_vector.cpp
 create mode 100644 Add Code Here/C++/Important_STL_properties/important_function_of_sets.cpp

diff --git a/Add Code Here/C++/Important_STL_properties/Important_stl_and_function_array.cpp b/Add Code Here/C++/Important_STL_properties/Important_stl_and_function_array.cpp
new file mode 100644
index 00000000000..28748a4ea93
--- /dev/null
+++ b/Add Code Here/C++/Important_STL_properties/Important_stl_and_function_array.cpp	
@@ -0,0 +1,169 @@
+#include <bits/stdc++.h>
+using namespace std;
+int main()
+{
+    int a[10] = {11, 23, 53, 64, 75, 16, 27, 88, 69, 10}; // array of size 10
+
+    // 1. sort
+    sort(a, a + 10); // sort(starting address, ending address)
+    for (int i = 0; i < 10; i++)
+    {
+        cout << a[i] << " ";
+    }
+    cout << endl;
+
+    // 2. reverse
+    reverse(a, a + 10); // reverse(starting address, ending address)
+    for (int i = 0; i < 10; i++)
+    {
+        cout << a[i] << " ";
+    }
+    cout << endl;
+
+    // 3. min_element
+    cout << *min_element(a, a + 10) << endl; // min_element(starting address, ending address)
+
+    // 4. max_element
+    cout << *max_element(a, a + 10) << endl; // max_element(starting address, ending address)
+
+    // 5. accumulate
+    cout << accumulate(a, a + 10, 0) << endl; // accumulate(starting address, ending address, initial value)
+
+    // 6. count
+    cout << count(a, a + 10, 10) << endl; // count(starting address, ending address, element to be counted)
+
+    // 7. find
+    cout << *find(a, a + 10, 10) << endl; // find(starting address, ending address, element to be found)
+
+    // 8. binary_search
+    cout << binary_search(a, a + 10, 10) << endl; // binary_search(starting address, ending address, element to be found)
+
+    // 9. lower_bound
+    cout << *lower_bound(a, a + 10, 10) << endl; // lower_bound(starting address, ending address, element to be found)
+
+    // 10. upper_bound
+    cout << *upper_bound(a, a + 10, 10) << endl; // upper_bound(starting address, ending address, element to be found)
+
+    // 11. rotate
+    rotate(a, a + 3, a + 10); // rotate(starting address, new starting address, ending address)
+    for (int i = 0; i < 10; i++)
+    {
+        cout << a[i] << " ";
+    }
+    cout << endl;
+
+    // 12. next_permutation
+    next_permutation(a, a + 10); // next_permutation(starting address, ending address)
+    for (int i = 0; i < 10; i++)
+    {
+        cout << a[i] << " ";
+    }
+    cout << endl;
+
+    // 13. prev_permutation
+    prev_permutation(a, a + 10); // prev_permutation(starting address, ending address)
+    for (int i = 0; i < 10; i++)
+    {
+        cout << a[i] << " ";
+    }
+    cout << endl;
+
+    // 14. swap
+    swap(a[0], a[9]); // swap(element 1, element 2)
+    for (int i = 0; i < 10; i++)
+    {
+        cout << a[i] << " ";
+    }
+    cout << endl;
+
+    // 15. swap_ranges
+    swap_ranges(a, a + 5, a + 5); // swap_ranges(starting address 1, ending address 1, starting address 2)
+    for (int i = 0; i < 10; i++)
+    {
+        cout << a[i] << " ";
+    }
+    cout << endl;
+
+    // 16. reverse_copy
+    reverse_copy(a, a + 10, a); // reverse_copy(starting address, ending address, starting address)
+    for (int i = 0; i < 10; i++)
+    {
+        cout << a[i] << " ";
+    }
+    cout << endl;
+
+    // 17. rotate_copy
+    rotate_copy(a, a + 3, a + 10, a); // rotate_copy(starting address, new starting address, ending address, starting address)
+    for (int i = 0; i < 10; i++)
+    {
+        cout << a[i] << " ";
+    }
+    cout << endl;
+
+    // 18. is_sorted
+    cout << is_sorted(a, a + 10) << endl; // is_sorted(starting address, ending address)
+
+    // 19. is_partitioned
+    cout << is_partitioned(a, a + 10, [](int x)
+                           { return x % 2 == 0; })
+         << endl; // is_partitioned(starting address, ending address, condition)
+
+    // 20. partition
+    partition(a, a + 10, [](int x)
+              { return x % 2 == 0; }); // partition(starting address, ending address, condition)
+    for (int i = 0; i < 10; i++)
+    {
+        cout << a[i] << " ";
+    }
+    cout << endl;
+
+    // 21. stable_partition
+    stable_partition(a, a + 10, [](int x)
+                     { return x % 2 == 0; }); // stable_partition(starting address, ending address, condition)
+    for (int i = 0; i < 10; i++)
+    {
+        cout << a[i] << " ";
+    }
+    cout << endl;
+
+    // 22. partition_point
+    auto it = partition_point(a, a + 10, [](int x)
+                              { return x % 2 == 0; }); // partition_point(starting address, ending address, condition)
+    cout << *it << endl;
+
+    // 23. random_shuffle
+    random_shuffle(a, a + 10); // random_shuffle(starting address, ending address)
+
+    // 24. shuffle
+    shuffle(a, a + 10, default_random_engine()); // shuffle(starting address, ending address, random engine)
+
+    // 25. max
+    cout << max(2, 3) << endl; // max(element 1, element 2)
+
+    // 26. min
+    cout << min(2, 3) << endl; // min(element 1, element 2)
+
+    // 27. memset
+    int b[10];
+    memset(b, 0, sizeof(b)); // memset(starting address, value to be filled, size of the array)
+
+    // 28. is_permutation
+    cout << is_permutation(a, a + 10, b) << endl; // is_permutation(starting address 1, ending address 1, starting address 2)
+
+    // 29. next
+    auto it = std::next(std::begin(a), 1); // get iterator to second element of array a
+
+    // 30. prev
+    auto it = std::prev(std::end(a), 1); // get iterator to last element of array a
+
+    // 31. iota
+    iota(a, a + 10, 1); // iota(starting address, ending address, value to be filled)
+
+    // 32. gcd
+    cout << __gcd(10, 20) << endl; // __gcd(element 1, element 2)//info: __gcd is a inbuilt function for finding gcd of two numbers
+
+    // 33. lcm
+    cout << lcm(10, 20) << endl; // lcm(element 1, element 2)
+
+    return 0;
+}
\ No newline at end of file
diff --git a/Add Code Here/C++/Important_STL_properties/Important_stl_and_function_string.cpp b/Add Code Here/C++/Important_STL_properties/Important_stl_and_function_string.cpp
new file mode 100644
index 00000000000..02c5173aa28
--- /dev/null
+++ b/Add Code Here/C++/Important_STL_properties/Important_stl_and_function_string.cpp	
@@ -0,0 +1,192 @@
+#include <bits/stdc++.h>
+using namespace std;
+int main()
+{
+    string s = "Hello World";
+    cout << s << endl;
+
+    // 1. sort
+    sort(s.begin(), s.end()); // sort(starting address, ending address)
+    cout << s << endl;
+
+    // 2. reverse
+    reverse(s.begin(), s.end()); // reverse(starting address, ending address)
+    cout << s << endl;
+
+    // 3. min_element
+    cout << *min_element(s.begin(), s.end()) << endl; // min_element(starting address, ending address)
+
+    // 4. max_element
+    cout << *max_element(s.begin(), s.end()) << endl; // max_element(starting address, ending address)
+
+    // 5. accumulate
+    cout << accumulate(s.begin(), s.end(), 0) << endl; // accumulate(starting address, ending address, initial value)//info: accumulate() is used to find the sum of elements in a container.
+
+    // 6. count
+    cout << count(s.begin(), s.end(), 'l') << endl; // count(starting address, ending address, element to be counted) //info: count() is used to count the number of occurrences of an element in a container.
+
+    // 7. find
+    cout << *find(s.begin(), s.end(), 'l') << endl; // find(starting address, ending address, element to be found)//info: find() is used to find the first occurrence of an element in a container.
+
+    // 8. binary_search
+    cout << binary_search(s.begin(), s.end(), 'l') << endl; // binary_search(starting address, ending address, element to be found)
+
+    // 9. lower_bound
+    cout << *lower_bound(s.begin(), s.end(), 'l') << endl; // lower_bound(starting address, ending address, element to be found)//info: lower_bound() is used to find the position of the first element in a container which is not less than a specified value.
+
+    // 10. upper_bound
+    cout << *upper_bound(s.begin(), s.end(), 'l') << endl; // upper_bound(starting address, ending address, element to be found)
+
+    // 11. rotate
+    rotate(s.begin(), s.begin() + 3, s.end()); // rotate(starting address, new starting address, ending address)
+    cout << s << endl;
+
+    // 12. next_permutation
+    next_permutation(s.begin(), s.end()); // next_permutation(starting address, ending address)
+    cout << s << endl;
+
+    // 13. substr
+    cout << s.substr(3, 4) << endl; // substr(starting index, length)
+
+    // 14. find_first_of
+    cout << s.find_first_of("l") << endl; // find_first_of(string to be found)
+
+    // 15. find_last_of
+    cout << s.find_last_of("l") << endl; // find_last_of(string to be found)
+
+    // 16. find_first_not_of
+    cout << s.find_first_not_of("l") << endl; // find_first_not_of(string to be found)
+
+    // 17. find_last_not_of
+    cout << s.find_last_not_of("l") << endl; // find_last_not_of(string to be found)
+
+    // 18. stoi
+    string s1 = "123";
+    cout << stoi(s1) << endl; // stoi(string to be converted)
+
+    // 19. to_string
+    int x = 123;
+    cout << to_string(x) << endl; // to_string(int to be converted)
+
+    // 20. isdigit
+    cout << isdigit(s[0]) << endl; // isdigit(character to be checked)
+
+    // 21. isalpha
+    cout << isalpha(s[0]) << endl; // isalpha(character to be checked)
+
+    // 22. isalnum
+    cout << isalnum(s[0]) << endl; // isalnum(character to be checked)
+
+    // 23. islower
+    cout << islower(s[0]) << endl; // islower(character to be checked)
+
+    // 24. isupper
+    cout << isupper(s[0]) << endl; // isupper(character to be checked)
+
+    // 25. isxdigit
+    cout << isxdigit(s[0]) << endl; // isxdigit(character to be checked)
+
+    // 26. isgraph
+    cout << isgraph(s[0]) << endl; // isgraph(character to be checked)
+
+    // 27. isprint
+    cout << isprint(s[0]) << endl; // isprint(character to be checked)
+
+    // 28. iscntrl
+    cout << iscntrl(s[0]) << endl; // iscntrl(character to be checked)
+
+    // 29. isspace
+    cout << isspace(s[0]) << endl; // isspace(character to be checked)
+
+    // 30. isblank
+    cout << isblank(s[0]) << endl; // isblank(character to be checked)
+
+    // 31. ispunct
+    cout << ispunct(s[0]) << endl; // ispunct(character to be checked)
+
+    // 32. toupper
+    cout << toupper(s[0]) << endl; // toupper(character to be converted)
+
+    // 33. tolower
+    cout << tolower(s[0]) << endl; // tolower(character to be converted)
+
+    // 34. getline
+    getline(cin, s); // getline(input stream, string)
+
+    // 35. stringstream
+    stringstream ss;
+    ss << s; // ss << string
+    ss >> s; // ss >> string
+
+    // 36. stringstream
+    stringstream ss1(s); // ss(string)
+
+    // 37. stringstream
+    stringstream ss2(s, ios_base::in | ios_base::out); // ss(string, mode)
+
+    // 38. stringstream
+    stringstream ss3(s, ios_base::in); // ss(string, mode)
+
+    // 39. stringstream
+    stringstream ss4(s, ios_base::out); // ss(string, mode)
+
+    // 40. stringstream
+    stringstream ss5(ios_base::in | ios_base::out); // ss(mode)
+
+    // 41. stringstream
+    stringstream ss6(ios_base::in); // ss(mode)
+
+    // 42. stringstream
+    stringstream ss7(ios_base::out); // ss(mode)
+
+    // 43. stringstream
+    stringstream ss8; // ss
+
+    // 44. stringstream
+    stringstream ss9(ios_base::app); // ss(mode)
+
+    // 45. stringstream
+    stringstream ss10(ios_base::ate); // ss(mode)
+
+    // 46. stringstream
+    stringstream ss11(ios_base::binary); // ss(mode)
+
+    // 47. stringstream
+    stringstream ss12(ios_base::trunc); // ss(mode)
+
+    // 48. stringstream
+    stringstream ss13(ios_base::in | ios_base::out | ios_base::binary); // ss(mode)
+
+    // 49. stringstream
+    stringstream ss14(ios_base::in | ios_base::out | ios_base::ate); // ss(mode)
+
+    // 50. stringstream
+    stringstream ss15(ios_base::in | ios_base::out | ios_base::app); // ss(mode)
+
+    // 51. stringstream
+    stringstream ss16(ios_base::in | ios_base::out | ios_base::trunc); // ss(mode)
+
+    // 52. stringstream
+    stringstream ss17(ios_base::in | ios_base::out | ios_base::binary | ios_base::ate); // ss(mode)
+
+    // 53. stringstream
+    stringstream ss18(ios_base::in | ios_base::out | ios_base::binary | ios_base::app); // ss(mode)
+
+    // 54. stringstream
+    stringstream ss19(ios_base::in | ios_base::out | ios_base::binary | ios_base::trunc); // ss(mode)
+
+    // 55. stringstream
+    stringstream ss20(ios_base::in | ios_base::out | ios_base::binary | ios_base::ate | ios_base::app); // ss(mode)
+
+    // 56. stringstream
+    stringstream ss21(ios_base::in | ios_base::out | ios_base::binary | ios_base::ate | ios_base::trunc); // ss(mode)
+
+    // 57. stringstream
+    stringstream ss22(ios_base::in | ios_base::out | ios_base::binary | ios_base::app | ios_base::trunc); // ss(mode)
+
+    // 58. stringstream
+    stringstream ss23(ios_base::in | ios_base::out | ios_base::binary | ios_base::ate | ios_base::app | ios_base::trunc); // ss(mode)
+
+    // 59.
+    return 0;
+}
\ No newline at end of file
diff --git a/Add Code Here/C++/Important_STL_properties/Important_stl_and_function_vector.cpp b/Add Code Here/C++/Important_STL_properties/Important_stl_and_function_vector.cpp
new file mode 100644
index 00000000000..b80e7a1429a
--- /dev/null
+++ b/Add Code Here/C++/Important_STL_properties/Important_stl_and_function_vector.cpp	
@@ -0,0 +1,389 @@
+#include <bits/stdc++.h>
+using namespace std;
+int main()
+{
+    vector<int> v5 = {11, 32, 53, 24, 65};
+    // sort
+    cout << "sort" << endl;
+    sort(v5.begin(), v5.end()); // sort in ascending order
+    for (auto i : v5)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+    sort(v5.begin(), v5.end(), greater<int>()); // sort in descending order
+    for (auto i : v5)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // permutation
+
+    vector<int> v = {1, 2, 3, 4, 5};
+    cout << "permutation" << endl;
+    // prev_permutation
+    prev_permutation(v.begin(), v.end()); // 1 2 3 5 4
+    for (auto i : v)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // next_permutation
+    next_permutation(v.begin(), v.end()); // 1 2 3 5 4
+    for (auto i : v)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // rotate
+    cout << "rotate" << endl;
+    rotate(v.begin(), v.begin() + 2, v.end()); // 3 5 4 1 2
+    for (auto i : v)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // reverse
+    cout << "reverse" << endl;
+    reverse(v.begin(), v.end()); // 2 1 4 5 3
+    for (auto i : v)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // accumulate
+    cout << "accumulate" << endl;
+    int sum = accumulate(v.begin(), v.end(), 0); // 15
+    cout << sum << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // count
+    cout << "count" << endl;
+    int cnt = count(v.begin(), v.end(), 1); // 1
+    cout << cnt << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // find
+    cout << "find" << endl;
+    auto it = find(v.begin(), v.end(), 1); // 1
+    cout << *it << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // binary_search
+    cout << "binary_search" << endl;
+    bool present = binary_search(v.begin(), v.end(), 1); // 1
+    cout << present << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // lower_bound
+    cout << "lower_bound" << endl;
+    auto it = lower_bound(v.begin(), v.end(), 1); // 1
+    cout << *it << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // upper_bound
+    cout << "upper_bound" << endl;
+    auto it = upper_bound(v.begin(), v.end(), 1); // 1
+    cout << *it << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // max_element
+    cout << "max_element" << endl;
+    auto it = max_element(v.begin(), v.end()); // 5
+    cout << *it << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // min_element
+    cout << "min_element" << endl;
+    auto it = min_element(v.begin(), v.end()); // 1
+    cout << *it << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // minmax_element
+    cout << "minmax_element" << endl;
+    auto it = minmax_element(v.begin(), v.end()); // 1 5
+    auto it1 = v.begin();
+    auto it2 = v.end() - 1;
+    cout << *it1 << " " << *it2 << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // is_sorted
+    cout << "is_sorted" << endl;
+    bool sorted = is_sorted(v.begin(), v.end()); // 0
+    cout << sorted << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // is_sorted_until
+    cout << "is_sorted_until" << endl;
+    auto it = is_sorted_until(v.begin(), v.end()); // 1 2
+    cout << *it << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // is_permutation
+    cout << "is_permutation" << endl;
+    vector<int> v1 = {1, 2, 3, 4, 5};
+    vector<int> v2 = {1, 2, 3, 4, 5};
+    bool permutation = is_permutation(v1.begin(), v1.end(), v2.begin()); // 1
+    cout << permutation << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // next_permutation
+    cout << "next_permutation" << endl;
+    next_permutation(v.begin(), v.end()); // 1 2 3 5 4
+    for (auto i : v)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // prev_permutation
+    cout << "prev_permutation" << endl;
+    prev_permutation(v.begin(), v.end()); // 1 2 3 4 5
+    for (auto i : v)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // swap
+    cout << "swap" << endl;
+    swap(v[0], v[1]); // 2 1 3 4 5
+    for (auto i : v)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // swap_ranges
+    cout << "swap_ranges" << endl;
+    swap_ranges(v.begin(), v.begin() + 2, v.end()); // 3 4 5 1 2
+    for (auto i : v)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // transform
+    cout << "transform" << endl;
+    transform(v.begin(), v.end(), v.begin(), [](int x)
+              { return x * x; }); // 9 16 25 1 4
+    for (auto i : v)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // fill
+    cout << "fill" << endl;
+    fill(v.begin(), v.end(), 5); // 5 5 5 5 5
+    for (auto i : v)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // remove
+    cout << "remove" << endl;
+    remove(v.begin(), v.end(), 5); // 5 5 5 5 5
+    for (auto i : v)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // remove_if
+    cout << "remove_if" << endl;
+    remove_if(v.begin(), v.end(), [](int x)
+              { return x % 2 == 0; }); // 5 5 5 5 5
+    for (auto i : v)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // remove_copy
+    cout << "remove_copy" << endl;
+    vector<int> v1(5);
+    remove_copy(v.begin(), v.end(), v1.begin(), 5); // 5 5 5 5 5
+    for (auto i : v1)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // remove_copy_if
+    cout << "remove_copy_if" << endl;
+    vector<int> v1(5);
+    remove_copy_if(v.begin(), v.end(), v1.begin(), [](int x)
+                   { return x % 2 == 0; }); // 5 5 5 5 5
+    for (auto i : v1)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // replace
+    cout << "replace" << endl;
+    replace(v.begin(), v.end(), 5, 1); // 1 1 1 1 1
+    for (auto i : v)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // replace_if
+    cout << "replace_if" << endl;
+    replace_if(
+        v.begin(), v.end(), [](int x)
+        { return x % 2 == 0; },
+        1); // 1 1 1 1 1
+    for (auto i : v)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // replace_copy
+    cout << "replace_copy" << endl;
+    vector<int> v1(5);
+    replace_copy(v.begin(), v.end(), v1.begin(), 5, 1); // 1 1 1 1 1
+    for (auto i : v1)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // replace_copy_if
+    cout << "replace_copy_if" << endl;
+    vector<int> v1(5);
+    replace_copy_if(
+        v.begin(), v.end(), v1.begin(), [](int x)
+        { return x % 2 == 0; },
+        1); // 1 1 1 1 1
+    for (auto i : v1)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // reverse
+    cout << "reverse" << endl;
+    reverse(v.begin(), v.end()); // 1 1 1 1 1
+    for (auto i : v)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // reverse_copy
+    cout << "reverse_copy" << endl;
+    vector<int> v1(5);
+    reverse_copy(v.begin(), v.end(), v1.begin()); // 1 1 1 1 1
+    for (auto i : v1)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // rotate_copy
+    cout << "rotate_copy" << endl;
+    vector<int> v1(5);
+    rotate_copy(v.begin(), v.begin() + 2, v.end(), v1.begin()); // 1 1 1 1 1
+    for (auto i : v1)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // random_shuffle
+    cout << "random_shuffle" << endl;
+    random_shuffle(v.begin(), v.end()); // 1 1 1 1 1
+    for (auto i : v)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // shuffle
+    cout << "shuffle" << endl;
+    shuffle(v.begin(), v.end(), default_random_engine()); // 1 1 1 1 1
+    for (auto i : v)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // unique
+    cout << "unique" << endl;
+    unique(v.begin(), v.end()); // 1 1 1 1 1
+    for (auto i : v)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // unique_copy
+    cout << "unique_copy" << endl;
+    vector<int> v1(5);
+    unique_copy(v.begin(), v.end(), v1.begin()); // 1 1 1 1 1
+    for (auto i : v1)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // is_partitioned
+    cout << "is_partitioned" << endl;
+    cout << is_partitioned(v.begin(), v.end(), [](int x)
+                           { return x % 2 == 0; })
+         << endl; // 1 1 1 1 1
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // partition
+    cout << "partition" << endl;
+    partition(v.begin(), v.end(), [](int x)
+              { return x % 2 == 0; }); // 1 1 1 1 1
+    for (auto i : v)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // partition_copy
+    cout << "partition_copy" << endl;
+    vector<int> v1(5), v2(5);
+    partition_copy(v.begin(), v.end(), v1.begin(), v2.begin(), [](int x)
+                   { return x % 2 == 0; }); // 1 1 1 1 1
+    for (auto i : v1)
+        cout << i << " ";
+    cout << endl;
+    for (auto i : v2)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // stable_partition
+    cout << "stable_partition" << endl;
+    stable_partition(v.begin(), v.end(), [](int x)
+                     { return x % 2 == 0; }); // 1 1 1 1 1
+    for (auto i : v)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // partition_point
+
+    cout << "partition_point" << endl;
+    cout << *partition_point(v.begin(), v.end(), [](int x)
+                             { return x % 2 == 0; })
+         << endl; // 1 1 1 1 1
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // stable_sort
+    cout << "stable_sort" << endl;
+    stable_sort(v.begin(), v.end()); // 1 1 1 1 1
+    for (auto i : v)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // partial_sort
+    cout << "partial_sort" << endl;
+    partial_sort(v.begin(), v.begin() + 2, v.end()); // 1 1 1 1 1
+    for (auto i : v)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // nth_element
+    cout << "nth_element" << endl;
+    nth_element(v.begin(), v.begin() + 2, v.end()); // 1 1 1 1 1
+    for (auto i : v)
+        cout << i << " ";
+    cout << endl;
+    cout << "----------------------------------------------------------------------" << endl;
+
+    // is_present
+    cout << "is_present" << endl;
+    cout << binary_search(v.begin(), v.end(), 3) << endl; // 1 1 1 1 1
+    cout << "----------------------------------------------------------------------" << endl;
+
+    return 0;
+}
\ No newline at end of file
diff --git a/Add Code Here/C++/Important_STL_properties/important_function_of_sets.cpp b/Add Code Here/C++/Important_STL_properties/important_function_of_sets.cpp
new file mode 100644
index 00000000000..0cdb8920a60
--- /dev/null
+++ b/Add Code Here/C++/Important_STL_properties/important_function_of_sets.cpp	
@@ -0,0 +1,78 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+int main()
+{
+    set<int> s;
+    s.insert(10);
+    s.insert(5);
+    s.insert(20);
+
+    // 1. sort
+    for (auto it = s.begin(); it != s.end(); it++)
+    {
+        cout << *it << " ";
+    }
+
+    cout << endl;
+
+    // 2. reverse
+    for (auto it = s.rbegin(); it != s.rend(); it++)
+    {
+        cout << *it << " ";
+    }
+
+    cout << endl;
+
+    // 3. min_element
+    cout << *min_element(s.begin(), s.end()) << endl;
+
+    // 4. max_element
+    cout << *max_element(s.begin(), s.end()) << endl;
+
+    // 5. accumulate
+    cout << accumulate(s.begin(), s.end(), 0) << endl;
+
+    // 6. count
+    cout << count(s.begin(), s.end(), 10) << endl;
+
+    // 7. find
+    cout << *find(s.begin(), s.end(), 10) << endl;
+
+    // 8. binary_search
+    cout << binary_search(s.begin(), s.end(), 10) << endl;
+
+    // 9. lower_bound
+    cout << *lower_bound(s.begin(), s.end(), 10) << endl;
+
+    // 10. upper_bound
+    cout << *upper_bound(s.begin(), s.end(), 10) << endl;
+
+    // // 11. rotate
+    // rotate(s.begin(), next(s.begin()), s.end());
+
+    // for (auto it = s.begin(); it != s.end(); it++)
+    // {
+    //     cout << *it << " ";
+    // }
+
+    // cout << endl;
+
+    // // 12. next_permutation
+    // next_permutation(s.begin(), s.end());
+    // for (auto it = s.begin(); it != s.end(); it++)
+    // {
+    //     cout << *it << " ";
+    // }
+
+    // cout << endl;
+
+    // // 13. prev_permutation
+    // prev_permutation(s.begin(), s.end());
+    // for (auto it = s.begin(); it != s.end(); it++)
+    // {
+    //     cout << *it << " ";
+    // }
+
+    return 0;
+}
\ No newline at end of file

From 639c2b870e3f15f7931a2089e2f0f177e830acc6 Mon Sep 17 00:00:00 2001
From: PRATHAMESH CHOUGALE
 <106848418+Prathamesh-chougale-17@users.noreply.github.com>
Date: Tue, 31 Oct 2023 16:01:28 +0530
Subject: [PATCH 2/3] Delete Add Code Here/C++/Important_STL_properties
 directory

---
 .../Important_stl_and_function_array.cpp      | 169 --------
 .../Important_stl_and_function_string.cpp     | 192 ---------
 .../Important_stl_and_function_vector.cpp     | 389 ------------------
 .../important_function_of_sets.cpp            |  78 ----
 4 files changed, 828 deletions(-)
 delete mode 100644 Add Code Here/C++/Important_STL_properties/Important_stl_and_function_array.cpp
 delete mode 100644 Add Code Here/C++/Important_STL_properties/Important_stl_and_function_string.cpp
 delete mode 100644 Add Code Here/C++/Important_STL_properties/Important_stl_and_function_vector.cpp
 delete mode 100644 Add Code Here/C++/Important_STL_properties/important_function_of_sets.cpp

diff --git a/Add Code Here/C++/Important_STL_properties/Important_stl_and_function_array.cpp b/Add Code Here/C++/Important_STL_properties/Important_stl_and_function_array.cpp
deleted file mode 100644
index 28748a4ea93..00000000000
--- a/Add Code Here/C++/Important_STL_properties/Important_stl_and_function_array.cpp	
+++ /dev/null
@@ -1,169 +0,0 @@
-#include <bits/stdc++.h>
-using namespace std;
-int main()
-{
-    int a[10] = {11, 23, 53, 64, 75, 16, 27, 88, 69, 10}; // array of size 10
-
-    // 1. sort
-    sort(a, a + 10); // sort(starting address, ending address)
-    for (int i = 0; i < 10; i++)
-    {
-        cout << a[i] << " ";
-    }
-    cout << endl;
-
-    // 2. reverse
-    reverse(a, a + 10); // reverse(starting address, ending address)
-    for (int i = 0; i < 10; i++)
-    {
-        cout << a[i] << " ";
-    }
-    cout << endl;
-
-    // 3. min_element
-    cout << *min_element(a, a + 10) << endl; // min_element(starting address, ending address)
-
-    // 4. max_element
-    cout << *max_element(a, a + 10) << endl; // max_element(starting address, ending address)
-
-    // 5. accumulate
-    cout << accumulate(a, a + 10, 0) << endl; // accumulate(starting address, ending address, initial value)
-
-    // 6. count
-    cout << count(a, a + 10, 10) << endl; // count(starting address, ending address, element to be counted)
-
-    // 7. find
-    cout << *find(a, a + 10, 10) << endl; // find(starting address, ending address, element to be found)
-
-    // 8. binary_search
-    cout << binary_search(a, a + 10, 10) << endl; // binary_search(starting address, ending address, element to be found)
-
-    // 9. lower_bound
-    cout << *lower_bound(a, a + 10, 10) << endl; // lower_bound(starting address, ending address, element to be found)
-
-    // 10. upper_bound
-    cout << *upper_bound(a, a + 10, 10) << endl; // upper_bound(starting address, ending address, element to be found)
-
-    // 11. rotate
-    rotate(a, a + 3, a + 10); // rotate(starting address, new starting address, ending address)
-    for (int i = 0; i < 10; i++)
-    {
-        cout << a[i] << " ";
-    }
-    cout << endl;
-
-    // 12. next_permutation
-    next_permutation(a, a + 10); // next_permutation(starting address, ending address)
-    for (int i = 0; i < 10; i++)
-    {
-        cout << a[i] << " ";
-    }
-    cout << endl;
-
-    // 13. prev_permutation
-    prev_permutation(a, a + 10); // prev_permutation(starting address, ending address)
-    for (int i = 0; i < 10; i++)
-    {
-        cout << a[i] << " ";
-    }
-    cout << endl;
-
-    // 14. swap
-    swap(a[0], a[9]); // swap(element 1, element 2)
-    for (int i = 0; i < 10; i++)
-    {
-        cout << a[i] << " ";
-    }
-    cout << endl;
-
-    // 15. swap_ranges
-    swap_ranges(a, a + 5, a + 5); // swap_ranges(starting address 1, ending address 1, starting address 2)
-    for (int i = 0; i < 10; i++)
-    {
-        cout << a[i] << " ";
-    }
-    cout << endl;
-
-    // 16. reverse_copy
-    reverse_copy(a, a + 10, a); // reverse_copy(starting address, ending address, starting address)
-    for (int i = 0; i < 10; i++)
-    {
-        cout << a[i] << " ";
-    }
-    cout << endl;
-
-    // 17. rotate_copy
-    rotate_copy(a, a + 3, a + 10, a); // rotate_copy(starting address, new starting address, ending address, starting address)
-    for (int i = 0; i < 10; i++)
-    {
-        cout << a[i] << " ";
-    }
-    cout << endl;
-
-    // 18. is_sorted
-    cout << is_sorted(a, a + 10) << endl; // is_sorted(starting address, ending address)
-
-    // 19. is_partitioned
-    cout << is_partitioned(a, a + 10, [](int x)
-                           { return x % 2 == 0; })
-         << endl; // is_partitioned(starting address, ending address, condition)
-
-    // 20. partition
-    partition(a, a + 10, [](int x)
-              { return x % 2 == 0; }); // partition(starting address, ending address, condition)
-    for (int i = 0; i < 10; i++)
-    {
-        cout << a[i] << " ";
-    }
-    cout << endl;
-
-    // 21. stable_partition
-    stable_partition(a, a + 10, [](int x)
-                     { return x % 2 == 0; }); // stable_partition(starting address, ending address, condition)
-    for (int i = 0; i < 10; i++)
-    {
-        cout << a[i] << " ";
-    }
-    cout << endl;
-
-    // 22. partition_point
-    auto it = partition_point(a, a + 10, [](int x)
-                              { return x % 2 == 0; }); // partition_point(starting address, ending address, condition)
-    cout << *it << endl;
-
-    // 23. random_shuffle
-    random_shuffle(a, a + 10); // random_shuffle(starting address, ending address)
-
-    // 24. shuffle
-    shuffle(a, a + 10, default_random_engine()); // shuffle(starting address, ending address, random engine)
-
-    // 25. max
-    cout << max(2, 3) << endl; // max(element 1, element 2)
-
-    // 26. min
-    cout << min(2, 3) << endl; // min(element 1, element 2)
-
-    // 27. memset
-    int b[10];
-    memset(b, 0, sizeof(b)); // memset(starting address, value to be filled, size of the array)
-
-    // 28. is_permutation
-    cout << is_permutation(a, a + 10, b) << endl; // is_permutation(starting address 1, ending address 1, starting address 2)
-
-    // 29. next
-    auto it = std::next(std::begin(a), 1); // get iterator to second element of array a
-
-    // 30. prev
-    auto it = std::prev(std::end(a), 1); // get iterator to last element of array a
-
-    // 31. iota
-    iota(a, a + 10, 1); // iota(starting address, ending address, value to be filled)
-
-    // 32. gcd
-    cout << __gcd(10, 20) << endl; // __gcd(element 1, element 2)//info: __gcd is a inbuilt function for finding gcd of two numbers
-
-    // 33. lcm
-    cout << lcm(10, 20) << endl; // lcm(element 1, element 2)
-
-    return 0;
-}
\ No newline at end of file
diff --git a/Add Code Here/C++/Important_STL_properties/Important_stl_and_function_string.cpp b/Add Code Here/C++/Important_STL_properties/Important_stl_and_function_string.cpp
deleted file mode 100644
index 02c5173aa28..00000000000
--- a/Add Code Here/C++/Important_STL_properties/Important_stl_and_function_string.cpp	
+++ /dev/null
@@ -1,192 +0,0 @@
-#include <bits/stdc++.h>
-using namespace std;
-int main()
-{
-    string s = "Hello World";
-    cout << s << endl;
-
-    // 1. sort
-    sort(s.begin(), s.end()); // sort(starting address, ending address)
-    cout << s << endl;
-
-    // 2. reverse
-    reverse(s.begin(), s.end()); // reverse(starting address, ending address)
-    cout << s << endl;
-
-    // 3. min_element
-    cout << *min_element(s.begin(), s.end()) << endl; // min_element(starting address, ending address)
-
-    // 4. max_element
-    cout << *max_element(s.begin(), s.end()) << endl; // max_element(starting address, ending address)
-
-    // 5. accumulate
-    cout << accumulate(s.begin(), s.end(), 0) << endl; // accumulate(starting address, ending address, initial value)//info: accumulate() is used to find the sum of elements in a container.
-
-    // 6. count
-    cout << count(s.begin(), s.end(), 'l') << endl; // count(starting address, ending address, element to be counted) //info: count() is used to count the number of occurrences of an element in a container.
-
-    // 7. find
-    cout << *find(s.begin(), s.end(), 'l') << endl; // find(starting address, ending address, element to be found)//info: find() is used to find the first occurrence of an element in a container.
-
-    // 8. binary_search
-    cout << binary_search(s.begin(), s.end(), 'l') << endl; // binary_search(starting address, ending address, element to be found)
-
-    // 9. lower_bound
-    cout << *lower_bound(s.begin(), s.end(), 'l') << endl; // lower_bound(starting address, ending address, element to be found)//info: lower_bound() is used to find the position of the first element in a container which is not less than a specified value.
-
-    // 10. upper_bound
-    cout << *upper_bound(s.begin(), s.end(), 'l') << endl; // upper_bound(starting address, ending address, element to be found)
-
-    // 11. rotate
-    rotate(s.begin(), s.begin() + 3, s.end()); // rotate(starting address, new starting address, ending address)
-    cout << s << endl;
-
-    // 12. next_permutation
-    next_permutation(s.begin(), s.end()); // next_permutation(starting address, ending address)
-    cout << s << endl;
-
-    // 13. substr
-    cout << s.substr(3, 4) << endl; // substr(starting index, length)
-
-    // 14. find_first_of
-    cout << s.find_first_of("l") << endl; // find_first_of(string to be found)
-
-    // 15. find_last_of
-    cout << s.find_last_of("l") << endl; // find_last_of(string to be found)
-
-    // 16. find_first_not_of
-    cout << s.find_first_not_of("l") << endl; // find_first_not_of(string to be found)
-
-    // 17. find_last_not_of
-    cout << s.find_last_not_of("l") << endl; // find_last_not_of(string to be found)
-
-    // 18. stoi
-    string s1 = "123";
-    cout << stoi(s1) << endl; // stoi(string to be converted)
-
-    // 19. to_string
-    int x = 123;
-    cout << to_string(x) << endl; // to_string(int to be converted)
-
-    // 20. isdigit
-    cout << isdigit(s[0]) << endl; // isdigit(character to be checked)
-
-    // 21. isalpha
-    cout << isalpha(s[0]) << endl; // isalpha(character to be checked)
-
-    // 22. isalnum
-    cout << isalnum(s[0]) << endl; // isalnum(character to be checked)
-
-    // 23. islower
-    cout << islower(s[0]) << endl; // islower(character to be checked)
-
-    // 24. isupper
-    cout << isupper(s[0]) << endl; // isupper(character to be checked)
-
-    // 25. isxdigit
-    cout << isxdigit(s[0]) << endl; // isxdigit(character to be checked)
-
-    // 26. isgraph
-    cout << isgraph(s[0]) << endl; // isgraph(character to be checked)
-
-    // 27. isprint
-    cout << isprint(s[0]) << endl; // isprint(character to be checked)
-
-    // 28. iscntrl
-    cout << iscntrl(s[0]) << endl; // iscntrl(character to be checked)
-
-    // 29. isspace
-    cout << isspace(s[0]) << endl; // isspace(character to be checked)
-
-    // 30. isblank
-    cout << isblank(s[0]) << endl; // isblank(character to be checked)
-
-    // 31. ispunct
-    cout << ispunct(s[0]) << endl; // ispunct(character to be checked)
-
-    // 32. toupper
-    cout << toupper(s[0]) << endl; // toupper(character to be converted)
-
-    // 33. tolower
-    cout << tolower(s[0]) << endl; // tolower(character to be converted)
-
-    // 34. getline
-    getline(cin, s); // getline(input stream, string)
-
-    // 35. stringstream
-    stringstream ss;
-    ss << s; // ss << string
-    ss >> s; // ss >> string
-
-    // 36. stringstream
-    stringstream ss1(s); // ss(string)
-
-    // 37. stringstream
-    stringstream ss2(s, ios_base::in | ios_base::out); // ss(string, mode)
-
-    // 38. stringstream
-    stringstream ss3(s, ios_base::in); // ss(string, mode)
-
-    // 39. stringstream
-    stringstream ss4(s, ios_base::out); // ss(string, mode)
-
-    // 40. stringstream
-    stringstream ss5(ios_base::in | ios_base::out); // ss(mode)
-
-    // 41. stringstream
-    stringstream ss6(ios_base::in); // ss(mode)
-
-    // 42. stringstream
-    stringstream ss7(ios_base::out); // ss(mode)
-
-    // 43. stringstream
-    stringstream ss8; // ss
-
-    // 44. stringstream
-    stringstream ss9(ios_base::app); // ss(mode)
-
-    // 45. stringstream
-    stringstream ss10(ios_base::ate); // ss(mode)
-
-    // 46. stringstream
-    stringstream ss11(ios_base::binary); // ss(mode)
-
-    // 47. stringstream
-    stringstream ss12(ios_base::trunc); // ss(mode)
-
-    // 48. stringstream
-    stringstream ss13(ios_base::in | ios_base::out | ios_base::binary); // ss(mode)
-
-    // 49. stringstream
-    stringstream ss14(ios_base::in | ios_base::out | ios_base::ate); // ss(mode)
-
-    // 50. stringstream
-    stringstream ss15(ios_base::in | ios_base::out | ios_base::app); // ss(mode)
-
-    // 51. stringstream
-    stringstream ss16(ios_base::in | ios_base::out | ios_base::trunc); // ss(mode)
-
-    // 52. stringstream
-    stringstream ss17(ios_base::in | ios_base::out | ios_base::binary | ios_base::ate); // ss(mode)
-
-    // 53. stringstream
-    stringstream ss18(ios_base::in | ios_base::out | ios_base::binary | ios_base::app); // ss(mode)
-
-    // 54. stringstream
-    stringstream ss19(ios_base::in | ios_base::out | ios_base::binary | ios_base::trunc); // ss(mode)
-
-    // 55. stringstream
-    stringstream ss20(ios_base::in | ios_base::out | ios_base::binary | ios_base::ate | ios_base::app); // ss(mode)
-
-    // 56. stringstream
-    stringstream ss21(ios_base::in | ios_base::out | ios_base::binary | ios_base::ate | ios_base::trunc); // ss(mode)
-
-    // 57. stringstream
-    stringstream ss22(ios_base::in | ios_base::out | ios_base::binary | ios_base::app | ios_base::trunc); // ss(mode)
-
-    // 58. stringstream
-    stringstream ss23(ios_base::in | ios_base::out | ios_base::binary | ios_base::ate | ios_base::app | ios_base::trunc); // ss(mode)
-
-    // 59.
-    return 0;
-}
\ No newline at end of file
diff --git a/Add Code Here/C++/Important_STL_properties/Important_stl_and_function_vector.cpp b/Add Code Here/C++/Important_STL_properties/Important_stl_and_function_vector.cpp
deleted file mode 100644
index b80e7a1429a..00000000000
--- a/Add Code Here/C++/Important_STL_properties/Important_stl_and_function_vector.cpp	
+++ /dev/null
@@ -1,389 +0,0 @@
-#include <bits/stdc++.h>
-using namespace std;
-int main()
-{
-    vector<int> v5 = {11, 32, 53, 24, 65};
-    // sort
-    cout << "sort" << endl;
-    sort(v5.begin(), v5.end()); // sort in ascending order
-    for (auto i : v5)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-    sort(v5.begin(), v5.end(), greater<int>()); // sort in descending order
-    for (auto i : v5)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // permutation
-
-    vector<int> v = {1, 2, 3, 4, 5};
-    cout << "permutation" << endl;
-    // prev_permutation
-    prev_permutation(v.begin(), v.end()); // 1 2 3 5 4
-    for (auto i : v)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // next_permutation
-    next_permutation(v.begin(), v.end()); // 1 2 3 5 4
-    for (auto i : v)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // rotate
-    cout << "rotate" << endl;
-    rotate(v.begin(), v.begin() + 2, v.end()); // 3 5 4 1 2
-    for (auto i : v)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // reverse
-    cout << "reverse" << endl;
-    reverse(v.begin(), v.end()); // 2 1 4 5 3
-    for (auto i : v)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // accumulate
-    cout << "accumulate" << endl;
-    int sum = accumulate(v.begin(), v.end(), 0); // 15
-    cout << sum << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // count
-    cout << "count" << endl;
-    int cnt = count(v.begin(), v.end(), 1); // 1
-    cout << cnt << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // find
-    cout << "find" << endl;
-    auto it = find(v.begin(), v.end(), 1); // 1
-    cout << *it << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // binary_search
-    cout << "binary_search" << endl;
-    bool present = binary_search(v.begin(), v.end(), 1); // 1
-    cout << present << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // lower_bound
-    cout << "lower_bound" << endl;
-    auto it = lower_bound(v.begin(), v.end(), 1); // 1
-    cout << *it << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // upper_bound
-    cout << "upper_bound" << endl;
-    auto it = upper_bound(v.begin(), v.end(), 1); // 1
-    cout << *it << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // max_element
-    cout << "max_element" << endl;
-    auto it = max_element(v.begin(), v.end()); // 5
-    cout << *it << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // min_element
-    cout << "min_element" << endl;
-    auto it = min_element(v.begin(), v.end()); // 1
-    cout << *it << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // minmax_element
-    cout << "minmax_element" << endl;
-    auto it = minmax_element(v.begin(), v.end()); // 1 5
-    auto it1 = v.begin();
-    auto it2 = v.end() - 1;
-    cout << *it1 << " " << *it2 << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // is_sorted
-    cout << "is_sorted" << endl;
-    bool sorted = is_sorted(v.begin(), v.end()); // 0
-    cout << sorted << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // is_sorted_until
-    cout << "is_sorted_until" << endl;
-    auto it = is_sorted_until(v.begin(), v.end()); // 1 2
-    cout << *it << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // is_permutation
-    cout << "is_permutation" << endl;
-    vector<int> v1 = {1, 2, 3, 4, 5};
-    vector<int> v2 = {1, 2, 3, 4, 5};
-    bool permutation = is_permutation(v1.begin(), v1.end(), v2.begin()); // 1
-    cout << permutation << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // next_permutation
-    cout << "next_permutation" << endl;
-    next_permutation(v.begin(), v.end()); // 1 2 3 5 4
-    for (auto i : v)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // prev_permutation
-    cout << "prev_permutation" << endl;
-    prev_permutation(v.begin(), v.end()); // 1 2 3 4 5
-    for (auto i : v)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // swap
-    cout << "swap" << endl;
-    swap(v[0], v[1]); // 2 1 3 4 5
-    for (auto i : v)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // swap_ranges
-    cout << "swap_ranges" << endl;
-    swap_ranges(v.begin(), v.begin() + 2, v.end()); // 3 4 5 1 2
-    for (auto i : v)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // transform
-    cout << "transform" << endl;
-    transform(v.begin(), v.end(), v.begin(), [](int x)
-              { return x * x; }); // 9 16 25 1 4
-    for (auto i : v)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // fill
-    cout << "fill" << endl;
-    fill(v.begin(), v.end(), 5); // 5 5 5 5 5
-    for (auto i : v)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // remove
-    cout << "remove" << endl;
-    remove(v.begin(), v.end(), 5); // 5 5 5 5 5
-    for (auto i : v)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // remove_if
-    cout << "remove_if" << endl;
-    remove_if(v.begin(), v.end(), [](int x)
-              { return x % 2 == 0; }); // 5 5 5 5 5
-    for (auto i : v)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // remove_copy
-    cout << "remove_copy" << endl;
-    vector<int> v1(5);
-    remove_copy(v.begin(), v.end(), v1.begin(), 5); // 5 5 5 5 5
-    for (auto i : v1)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // remove_copy_if
-    cout << "remove_copy_if" << endl;
-    vector<int> v1(5);
-    remove_copy_if(v.begin(), v.end(), v1.begin(), [](int x)
-                   { return x % 2 == 0; }); // 5 5 5 5 5
-    for (auto i : v1)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // replace
-    cout << "replace" << endl;
-    replace(v.begin(), v.end(), 5, 1); // 1 1 1 1 1
-    for (auto i : v)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // replace_if
-    cout << "replace_if" << endl;
-    replace_if(
-        v.begin(), v.end(), [](int x)
-        { return x % 2 == 0; },
-        1); // 1 1 1 1 1
-    for (auto i : v)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // replace_copy
-    cout << "replace_copy" << endl;
-    vector<int> v1(5);
-    replace_copy(v.begin(), v.end(), v1.begin(), 5, 1); // 1 1 1 1 1
-    for (auto i : v1)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // replace_copy_if
-    cout << "replace_copy_if" << endl;
-    vector<int> v1(5);
-    replace_copy_if(
-        v.begin(), v.end(), v1.begin(), [](int x)
-        { return x % 2 == 0; },
-        1); // 1 1 1 1 1
-    for (auto i : v1)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // reverse
-    cout << "reverse" << endl;
-    reverse(v.begin(), v.end()); // 1 1 1 1 1
-    for (auto i : v)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // reverse_copy
-    cout << "reverse_copy" << endl;
-    vector<int> v1(5);
-    reverse_copy(v.begin(), v.end(), v1.begin()); // 1 1 1 1 1
-    for (auto i : v1)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // rotate_copy
-    cout << "rotate_copy" << endl;
-    vector<int> v1(5);
-    rotate_copy(v.begin(), v.begin() + 2, v.end(), v1.begin()); // 1 1 1 1 1
-    for (auto i : v1)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // random_shuffle
-    cout << "random_shuffle" << endl;
-    random_shuffle(v.begin(), v.end()); // 1 1 1 1 1
-    for (auto i : v)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // shuffle
-    cout << "shuffle" << endl;
-    shuffle(v.begin(), v.end(), default_random_engine()); // 1 1 1 1 1
-    for (auto i : v)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // unique
-    cout << "unique" << endl;
-    unique(v.begin(), v.end()); // 1 1 1 1 1
-    for (auto i : v)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // unique_copy
-    cout << "unique_copy" << endl;
-    vector<int> v1(5);
-    unique_copy(v.begin(), v.end(), v1.begin()); // 1 1 1 1 1
-    for (auto i : v1)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // is_partitioned
-    cout << "is_partitioned" << endl;
-    cout << is_partitioned(v.begin(), v.end(), [](int x)
-                           { return x % 2 == 0; })
-         << endl; // 1 1 1 1 1
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // partition
-    cout << "partition" << endl;
-    partition(v.begin(), v.end(), [](int x)
-              { return x % 2 == 0; }); // 1 1 1 1 1
-    for (auto i : v)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // partition_copy
-    cout << "partition_copy" << endl;
-    vector<int> v1(5), v2(5);
-    partition_copy(v.begin(), v.end(), v1.begin(), v2.begin(), [](int x)
-                   { return x % 2 == 0; }); // 1 1 1 1 1
-    for (auto i : v1)
-        cout << i << " ";
-    cout << endl;
-    for (auto i : v2)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // stable_partition
-    cout << "stable_partition" << endl;
-    stable_partition(v.begin(), v.end(), [](int x)
-                     { return x % 2 == 0; }); // 1 1 1 1 1
-    for (auto i : v)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // partition_point
-
-    cout << "partition_point" << endl;
-    cout << *partition_point(v.begin(), v.end(), [](int x)
-                             { return x % 2 == 0; })
-         << endl; // 1 1 1 1 1
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // stable_sort
-    cout << "stable_sort" << endl;
-    stable_sort(v.begin(), v.end()); // 1 1 1 1 1
-    for (auto i : v)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // partial_sort
-    cout << "partial_sort" << endl;
-    partial_sort(v.begin(), v.begin() + 2, v.end()); // 1 1 1 1 1
-    for (auto i : v)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // nth_element
-    cout << "nth_element" << endl;
-    nth_element(v.begin(), v.begin() + 2, v.end()); // 1 1 1 1 1
-    for (auto i : v)
-        cout << i << " ";
-    cout << endl;
-    cout << "----------------------------------------------------------------------" << endl;
-
-    // is_present
-    cout << "is_present" << endl;
-    cout << binary_search(v.begin(), v.end(), 3) << endl; // 1 1 1 1 1
-    cout << "----------------------------------------------------------------------" << endl;
-
-    return 0;
-}
\ No newline at end of file
diff --git a/Add Code Here/C++/Important_STL_properties/important_function_of_sets.cpp b/Add Code Here/C++/Important_STL_properties/important_function_of_sets.cpp
deleted file mode 100644
index 0cdb8920a60..00000000000
--- a/Add Code Here/C++/Important_STL_properties/important_function_of_sets.cpp	
+++ /dev/null
@@ -1,78 +0,0 @@
-#include <bits/stdc++.h>
-using namespace std;
-
-int main()
-{
-    set<int> s;
-    s.insert(10);
-    s.insert(5);
-    s.insert(20);
-
-    // 1. sort
-    for (auto it = s.begin(); it != s.end(); it++)
-    {
-        cout << *it << " ";
-    }
-
-    cout << endl;
-
-    // 2. reverse
-    for (auto it = s.rbegin(); it != s.rend(); it++)
-    {
-        cout << *it << " ";
-    }
-
-    cout << endl;
-
-    // 3. min_element
-    cout << *min_element(s.begin(), s.end()) << endl;
-
-    // 4. max_element
-    cout << *max_element(s.begin(), s.end()) << endl;
-
-    // 5. accumulate
-    cout << accumulate(s.begin(), s.end(), 0) << endl;
-
-    // 6. count
-    cout << count(s.begin(), s.end(), 10) << endl;
-
-    // 7. find
-    cout << *find(s.begin(), s.end(), 10) << endl;
-
-    // 8. binary_search
-    cout << binary_search(s.begin(), s.end(), 10) << endl;
-
-    // 9. lower_bound
-    cout << *lower_bound(s.begin(), s.end(), 10) << endl;
-
-    // 10. upper_bound
-    cout << *upper_bound(s.begin(), s.end(), 10) << endl;
-
-    // // 11. rotate
-    // rotate(s.begin(), next(s.begin()), s.end());
-
-    // for (auto it = s.begin(); it != s.end(); it++)
-    // {
-    //     cout << *it << " ";
-    // }
-
-    // cout << endl;
-
-    // // 12. next_permutation
-    // next_permutation(s.begin(), s.end());
-    // for (auto it = s.begin(); it != s.end(); it++)
-    // {
-    //     cout << *it << " ";
-    // }
-
-    // cout << endl;
-
-    // // 13. prev_permutation
-    // prev_permutation(s.begin(), s.end());
-    // for (auto it = s.begin(); it != s.end(); it++)
-    // {
-    //     cout << *it << " ";
-    // }
-
-    return 0;
-}
\ No newline at end of file

From e1676ff01b0009b2f1e5482b684a8bc5ff3d0f34 Mon Sep 17 00:00:00 2001
From: PRATHAMESH CHOUGALE
 <106848418+Prathamesh-chougale-17@users.noreply.github.com>
Date: Tue, 31 Oct 2023 16:03:22 +0530
Subject: [PATCH 3/3] Adding important stl functions and properties

---
 .../Important_stl_and_function_array.cpp      | 169 +++++++++++++++
 .../Important_stl_and_function_string.cpp     | 192 ++++++++++++++++++
 .../important_function_of_sets.cpp            |  78 +++++++
 3 files changed, 439 insertions(+)
 create mode 100644 Add Code Here/C++/Important_STL_properties/Important_stl_and_function_array.cpp
 create mode 100644 Add Code Here/C++/Important_STL_properties/Important_stl_and_function_string.cpp
 create mode 100644 Add Code Here/C++/Important_STL_properties/important_function_of_sets.cpp

diff --git a/Add Code Here/C++/Important_STL_properties/Important_stl_and_function_array.cpp b/Add Code Here/C++/Important_STL_properties/Important_stl_and_function_array.cpp
new file mode 100644
index 00000000000..df23c742b72
--- /dev/null
+++ b/Add Code Here/C++/Important_STL_properties/Important_stl_and_function_array.cpp	
@@ -0,0 +1,169 @@
+#include <bits/stdc++.h>
+using namespace std;
+int main()
+{
+    int a[10] = {11, 23, 53, 64, 75, 16, 27, 88, 69, 10}; // array of size 10
+
+    // 1. sort
+    sort(a, a + 10); // sort(starting address, ending address)
+    for (int i = 0; i < 10; i++)
+    {
+        cout << a[i] << " ";
+    }
+    cout << endl;
+
+    // 2. reverse
+    reverse(a, a + 10); // reverse(starting address, ending address)
+    for (int i = 0; i < 10; i++)
+    {
+        cout << a[i] << " ";
+    }
+    cout << endl;
+
+    // 3. min_element
+    cout << *min_element(a, a + 10) << endl; // min_element(starting address, ending address)
+
+    // 4. max_element
+    cout << *max_element(a, a + 10) << endl; // max_element(starting address, ending address)
+
+    // 5. accumulate
+    cout << accumulate(a, a + 10, 0) << endl; // accumulate(starting address, ending address, initial value)
+
+    // 6. count
+    cout << count(a, a + 10, 10) << endl; // count(starting address, ending address, element to be counted)
+
+    // 7. find
+    cout << *find(a, a + 10, 10) << endl; // find(starting address, ending address, element to be found)
+
+    // 8. binary_search
+    cout << binary_search(a, a + 10, 10) << endl; // binary_search(starting address, ending address, element to be found)
+
+    // 9. lower_bound
+    cout << *lower_bound(a, a + 10, 10) << endl; // lower_bound(starting address, ending address, element to be found)
+
+    // 10. upper_bound
+    cout << *upper_bound(a, a + 10, 10) << endl; // upper_bound(starting address, ending address, element to be found)
+
+    // 11. rotate
+    rotate(a, a + 3, a + 10); // rotate(starting address, new starting address, ending address)
+    for (int i = 0; i < 10; i++)
+    {
+        cout << a[i] << " ";
+    }
+    cout << endl;
+
+    // 12. next_permutation
+    next_permutation(a, a + 10); // next_permutation(starting address, ending address)
+    for (int i = 0; i < 10; i++)
+    {
+        cout << a[i] << " ";
+    }
+    cout << endl;
+
+    // 13. prev_permutation
+    prev_permutation(a, a + 10); // prev_permutation(starting address, ending address)
+    for (int i = 0; i < 10; i++)
+    {
+        cout << a[i] << " ";
+    }
+    cout << endl;
+
+    // 14. swap
+    swap(a[0], a[9]); // swap(element 1, element 2)
+    for (int i = 0; i < 10; i++)
+    {
+        cout << a[i] << " ";
+    }
+    cout << endl;
+
+    // 15. swap_ranges
+    swap_ranges(a, a + 5, a + 5); // swap_ranges(starting address 1, ending address 1, starting address 2)
+    for (int i = 0; i < 10; i++)
+    {
+        cout << a[i] << " ";
+    }
+    cout << endl;
+
+    // 16. reverse_copy
+    reverse_copy(a, a + 10, a); // reverse_copy(starting address, ending address, starting address)
+    for (int i = 0; i < 10; i++)
+    {
+        cout << a[i] << " ";
+    }
+    cout << endl;
+
+    // 17. rotate_copy
+    rotate_copy(a, a + 3, a + 10, a); // rotate_copy(starting address, new starting address, ending address, starting address)
+    for (int i = 0; i < 10; i++)
+    {
+        cout << a[i] << " ";
+    }
+    cout << endl;
+
+    // 18. is_sorted
+    cout << is_sorted(a, a + 10) << endl; // is_sorted(starting address, ending address)
+
+    // 19. is_partitioned
+    cout << is_partitioned(a, a + 10, [](int x)
+                           { return x % 2 == 0; })
+         << endl; // is_partitioned(starting address, ending address, condition)
+
+    // 20. partition
+    partition(a, a + 10, [](int x)
+              { return x % 2 == 0; }); // partition(starting address, ending address, condition)
+    for (int i = 0; i < 10; i++)
+    {
+        cout << a[i] << " ";
+    }
+    cout << endl;
+
+    // 21. stable_partition
+    stable_partition(a, a + 10, [](int x)
+                     { return x % 2 == 0; }); // stable_partition(starting address, ending address, condition)
+    for (int i = 0; i < 10; i++)
+    {
+        cout << a[i] << " ";
+    }
+    cout << endl;
+
+    // 22. partition_point
+    // auto it = partition_point(a, a + 10, [](int x)
+    //                           { return x % 2 == 0; }); // partition_point(starting address, ending address, condition)
+    // cout << *it << endl;
+
+    // 23. random_shuffle
+    random_shuffle(a, a + 10); // random_shuffle(starting address, ending address)
+
+    // 24. shuffle
+    shuffle(a, a + 10, default_random_engine()); // shuffle(starting address, ending address, random engine)
+
+    // 25. max
+    cout << max(2, 3) << endl; // max(element 1, element 2)
+
+    // 26. min
+    cout << min(2, 3) << endl; // min(element 1, element 2)
+
+    // 27. memset
+    int b[10];
+    memset(b, 0, sizeof(b)); // memset(starting address, value to be filled, size of the array)
+
+    // 28. is_permutation
+    cout << is_permutation(a, a + 10, b) << endl; // is_permutation(starting address 1, ending address 1, starting address 2)
+
+    // 29. next
+    // auto it = std::next(std::begin(a), 1); // get iterator to second element of array a
+
+    // 30. prev
+    // auto it = std::prev(std::end(a), 1); // get iterator to last element of array a
+
+    // 31. iota
+    iota(a, a + 10, 1); // iota(starting address, ending address, value to be filled)
+
+    // 32. gcd
+    cout << __gcd(10, 20) << endl; // __gcd(element 1, element 2)//info: __gcd is a inbuilt function for finding gcd of two numbers
+
+    // 33. lcm
+    // cout << lcm(10, 20) << endl; // lcm(element 1, element 2)
+
+    return 0;
+}
\ No newline at end of file
diff --git a/Add Code Here/C++/Important_STL_properties/Important_stl_and_function_string.cpp b/Add Code Here/C++/Important_STL_properties/Important_stl_and_function_string.cpp
new file mode 100644
index 00000000000..02c5173aa28
--- /dev/null
+++ b/Add Code Here/C++/Important_STL_properties/Important_stl_and_function_string.cpp	
@@ -0,0 +1,192 @@
+#include <bits/stdc++.h>
+using namespace std;
+int main()
+{
+    string s = "Hello World";
+    cout << s << endl;
+
+    // 1. sort
+    sort(s.begin(), s.end()); // sort(starting address, ending address)
+    cout << s << endl;
+
+    // 2. reverse
+    reverse(s.begin(), s.end()); // reverse(starting address, ending address)
+    cout << s << endl;
+
+    // 3. min_element
+    cout << *min_element(s.begin(), s.end()) << endl; // min_element(starting address, ending address)
+
+    // 4. max_element
+    cout << *max_element(s.begin(), s.end()) << endl; // max_element(starting address, ending address)
+
+    // 5. accumulate
+    cout << accumulate(s.begin(), s.end(), 0) << endl; // accumulate(starting address, ending address, initial value)//info: accumulate() is used to find the sum of elements in a container.
+
+    // 6. count
+    cout << count(s.begin(), s.end(), 'l') << endl; // count(starting address, ending address, element to be counted) //info: count() is used to count the number of occurrences of an element in a container.
+
+    // 7. find
+    cout << *find(s.begin(), s.end(), 'l') << endl; // find(starting address, ending address, element to be found)//info: find() is used to find the first occurrence of an element in a container.
+
+    // 8. binary_search
+    cout << binary_search(s.begin(), s.end(), 'l') << endl; // binary_search(starting address, ending address, element to be found)
+
+    // 9. lower_bound
+    cout << *lower_bound(s.begin(), s.end(), 'l') << endl; // lower_bound(starting address, ending address, element to be found)//info: lower_bound() is used to find the position of the first element in a container which is not less than a specified value.
+
+    // 10. upper_bound
+    cout << *upper_bound(s.begin(), s.end(), 'l') << endl; // upper_bound(starting address, ending address, element to be found)
+
+    // 11. rotate
+    rotate(s.begin(), s.begin() + 3, s.end()); // rotate(starting address, new starting address, ending address)
+    cout << s << endl;
+
+    // 12. next_permutation
+    next_permutation(s.begin(), s.end()); // next_permutation(starting address, ending address)
+    cout << s << endl;
+
+    // 13. substr
+    cout << s.substr(3, 4) << endl; // substr(starting index, length)
+
+    // 14. find_first_of
+    cout << s.find_first_of("l") << endl; // find_first_of(string to be found)
+
+    // 15. find_last_of
+    cout << s.find_last_of("l") << endl; // find_last_of(string to be found)
+
+    // 16. find_first_not_of
+    cout << s.find_first_not_of("l") << endl; // find_first_not_of(string to be found)
+
+    // 17. find_last_not_of
+    cout << s.find_last_not_of("l") << endl; // find_last_not_of(string to be found)
+
+    // 18. stoi
+    string s1 = "123";
+    cout << stoi(s1) << endl; // stoi(string to be converted)
+
+    // 19. to_string
+    int x = 123;
+    cout << to_string(x) << endl; // to_string(int to be converted)
+
+    // 20. isdigit
+    cout << isdigit(s[0]) << endl; // isdigit(character to be checked)
+
+    // 21. isalpha
+    cout << isalpha(s[0]) << endl; // isalpha(character to be checked)
+
+    // 22. isalnum
+    cout << isalnum(s[0]) << endl; // isalnum(character to be checked)
+
+    // 23. islower
+    cout << islower(s[0]) << endl; // islower(character to be checked)
+
+    // 24. isupper
+    cout << isupper(s[0]) << endl; // isupper(character to be checked)
+
+    // 25. isxdigit
+    cout << isxdigit(s[0]) << endl; // isxdigit(character to be checked)
+
+    // 26. isgraph
+    cout << isgraph(s[0]) << endl; // isgraph(character to be checked)
+
+    // 27. isprint
+    cout << isprint(s[0]) << endl; // isprint(character to be checked)
+
+    // 28. iscntrl
+    cout << iscntrl(s[0]) << endl; // iscntrl(character to be checked)
+
+    // 29. isspace
+    cout << isspace(s[0]) << endl; // isspace(character to be checked)
+
+    // 30. isblank
+    cout << isblank(s[0]) << endl; // isblank(character to be checked)
+
+    // 31. ispunct
+    cout << ispunct(s[0]) << endl; // ispunct(character to be checked)
+
+    // 32. toupper
+    cout << toupper(s[0]) << endl; // toupper(character to be converted)
+
+    // 33. tolower
+    cout << tolower(s[0]) << endl; // tolower(character to be converted)
+
+    // 34. getline
+    getline(cin, s); // getline(input stream, string)
+
+    // 35. stringstream
+    stringstream ss;
+    ss << s; // ss << string
+    ss >> s; // ss >> string
+
+    // 36. stringstream
+    stringstream ss1(s); // ss(string)
+
+    // 37. stringstream
+    stringstream ss2(s, ios_base::in | ios_base::out); // ss(string, mode)
+
+    // 38. stringstream
+    stringstream ss3(s, ios_base::in); // ss(string, mode)
+
+    // 39. stringstream
+    stringstream ss4(s, ios_base::out); // ss(string, mode)
+
+    // 40. stringstream
+    stringstream ss5(ios_base::in | ios_base::out); // ss(mode)
+
+    // 41. stringstream
+    stringstream ss6(ios_base::in); // ss(mode)
+
+    // 42. stringstream
+    stringstream ss7(ios_base::out); // ss(mode)
+
+    // 43. stringstream
+    stringstream ss8; // ss
+
+    // 44. stringstream
+    stringstream ss9(ios_base::app); // ss(mode)
+
+    // 45. stringstream
+    stringstream ss10(ios_base::ate); // ss(mode)
+
+    // 46. stringstream
+    stringstream ss11(ios_base::binary); // ss(mode)
+
+    // 47. stringstream
+    stringstream ss12(ios_base::trunc); // ss(mode)
+
+    // 48. stringstream
+    stringstream ss13(ios_base::in | ios_base::out | ios_base::binary); // ss(mode)
+
+    // 49. stringstream
+    stringstream ss14(ios_base::in | ios_base::out | ios_base::ate); // ss(mode)
+
+    // 50. stringstream
+    stringstream ss15(ios_base::in | ios_base::out | ios_base::app); // ss(mode)
+
+    // 51. stringstream
+    stringstream ss16(ios_base::in | ios_base::out | ios_base::trunc); // ss(mode)
+
+    // 52. stringstream
+    stringstream ss17(ios_base::in | ios_base::out | ios_base::binary | ios_base::ate); // ss(mode)
+
+    // 53. stringstream
+    stringstream ss18(ios_base::in | ios_base::out | ios_base::binary | ios_base::app); // ss(mode)
+
+    // 54. stringstream
+    stringstream ss19(ios_base::in | ios_base::out | ios_base::binary | ios_base::trunc); // ss(mode)
+
+    // 55. stringstream
+    stringstream ss20(ios_base::in | ios_base::out | ios_base::binary | ios_base::ate | ios_base::app); // ss(mode)
+
+    // 56. stringstream
+    stringstream ss21(ios_base::in | ios_base::out | ios_base::binary | ios_base::ate | ios_base::trunc); // ss(mode)
+
+    // 57. stringstream
+    stringstream ss22(ios_base::in | ios_base::out | ios_base::binary | ios_base::app | ios_base::trunc); // ss(mode)
+
+    // 58. stringstream
+    stringstream ss23(ios_base::in | ios_base::out | ios_base::binary | ios_base::ate | ios_base::app | ios_base::trunc); // ss(mode)
+
+    // 59.
+    return 0;
+}
\ No newline at end of file
diff --git a/Add Code Here/C++/Important_STL_properties/important_function_of_sets.cpp b/Add Code Here/C++/Important_STL_properties/important_function_of_sets.cpp
new file mode 100644
index 00000000000..0cdb8920a60
--- /dev/null
+++ b/Add Code Here/C++/Important_STL_properties/important_function_of_sets.cpp	
@@ -0,0 +1,78 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+int main()
+{
+    set<int> s;
+    s.insert(10);
+    s.insert(5);
+    s.insert(20);
+
+    // 1. sort
+    for (auto it = s.begin(); it != s.end(); it++)
+    {
+        cout << *it << " ";
+    }
+
+    cout << endl;
+
+    // 2. reverse
+    for (auto it = s.rbegin(); it != s.rend(); it++)
+    {
+        cout << *it << " ";
+    }
+
+    cout << endl;
+
+    // 3. min_element
+    cout << *min_element(s.begin(), s.end()) << endl;
+
+    // 4. max_element
+    cout << *max_element(s.begin(), s.end()) << endl;
+
+    // 5. accumulate
+    cout << accumulate(s.begin(), s.end(), 0) << endl;
+
+    // 6. count
+    cout << count(s.begin(), s.end(), 10) << endl;
+
+    // 7. find
+    cout << *find(s.begin(), s.end(), 10) << endl;
+
+    // 8. binary_search
+    cout << binary_search(s.begin(), s.end(), 10) << endl;
+
+    // 9. lower_bound
+    cout << *lower_bound(s.begin(), s.end(), 10) << endl;
+
+    // 10. upper_bound
+    cout << *upper_bound(s.begin(), s.end(), 10) << endl;
+
+    // // 11. rotate
+    // rotate(s.begin(), next(s.begin()), s.end());
+
+    // for (auto it = s.begin(); it != s.end(); it++)
+    // {
+    //     cout << *it << " ";
+    // }
+
+    // cout << endl;
+
+    // // 12. next_permutation
+    // next_permutation(s.begin(), s.end());
+    // for (auto it = s.begin(); it != s.end(); it++)
+    // {
+    //     cout << *it << " ";
+    // }
+
+    // cout << endl;
+
+    // // 13. prev_permutation
+    // prev_permutation(s.begin(), s.end());
+    // for (auto it = s.begin(); it != s.end(); it++)
+    // {
+    //     cout << *it << " ";
+    // }
+
+    return 0;
+}
\ No newline at end of file