leetcode: Add 0287

src/leetcode/0035.search-insert-position/src/main.rs

@@ -5,41 +5,68 @@
 use std::cmp::Ordering;
 
 // Binary search
-pub fn search_insert(nums: Vec<i32>, target: i32) -> i32 {
+pub fn search_insert1(nums: Vec<i32>, target: i32) -> i32 {
     assert!(!nums.is_empty());
 
-    let mut low = 0;
-    let mut high = nums.len() - 1;
-    while low + 1 < high {
-        let middle = low + (high - low) / 2;
+    if target < nums[0] {
+        return 0;
+    }
+    if target > nums[nums.len() - 1] {
+        return nums.len() as i32;
+    }
+
+    // 左闭右闭区间
+    let mut left: usize = 0;
+    let mut right: usize = nums.len() - 1;
+
+    // 终止循环的条件是 nums[left] > nums[right].
+    // 此时 left 所在位置就是 target 插入到数组中的位置.
+    while left <= right {
+        let middle = left + (right - left) / 2;
         match nums[middle].cmp(&target) {
-            Ordering::Less => low = middle,
+            Ordering::Less => left = middle + 1,
             Ordering::Equal => return middle as i32,
-            Ordering::Greater => high = middle,
+            Ordering::Greater => right = middle - 1,
         }
     }
-    if nums[high] < target {
-        high as i32 + 1
-    } else if nums[low] > target {
-        low as i32 - 1
-    } else {
-        high as i32
-    }
+
+    left as i32
 }
 
-fn main() {
+pub type SolutionFn = fn(Vec<i32>, i32) -> i32;
+
+fn check_solution(func: SolutionFn) {
     let nums = vec![1, 3, 5, 6];
     let target = 5;
-    let pos = search_insert(nums, target);
+    let pos = func(nums, target);
     assert_eq!(pos, 2);
 
     let nums = vec![1, 3, 5, 6];
     let target = 2;
-    let pos = search_insert(nums, target);
+    let pos = func(nums, target);
     assert_eq!(pos, 1);
 
     let nums = vec![1, 3, 5, 6];
     let target = 7;
-    let pos = search_insert(nums, target);
+    let pos = func(nums, target);
     assert_eq!(pos, 4);
+
+    let nums = vec![1, 3, 5, 6];
+    let target = 0;
+    let pos = func(nums, target);
+    assert_eq!(pos, 0);
+}
+
+fn main() {
+    check_solution(search_insert1);
+}
+
+#[cfg(test)]
+mod tests {
+    use super::{check_solution, search_insert1};
+
+    #[test]
+    fn test_search_insert1() {
+        check_solution(search_insert1);
+    }
 }

src/leetcode/0069.sqrtx/src/main.rs

@@ -2,21 +2,23 @@
 // Use of this source is governed by General Public License that can be found
 // in the LICENSE file.
 
-pub type SolutionFn = fn(i32) -> i32;
+use std::cmp::Ordering;
+
+// Binary Search
+pub fn my_sqrt1(x: i32) -> i32 {
+    assert!(x >= 0);
 
-pub fn my_sqrt(x: i32) -> i32 {
     if x == 0 || x == 1 {
         return x;
     }
 
-    let mut left = 0;
-    let mut right = x;
-    let mut middle: i32;
-    let mut ans = 0;
+    let mut left: i32 = 0;
+    let mut right: i32 = x;
+    let mut ans: i32 = 0;
     let x1 = x as i64;
 
     while left <= right {
-        middle = left + (right - left) / 2;
+        let middle: i32 = left + (right - left) / 2;
         let square = (middle as i64) * (middle as i64);
         if square > x1 {
             right = middle - 1;
@@ -46,10 +48,14 @@ pub fn my_sqrt2(x: i32) -> i32 {
 }
 
 pub fn my_sqrt3(x: i32) -> i32 {
-    use std::cmp::Ordering;
+    assert!(x >= 0);
 
-    let mut left = 1;
-    let mut right = x;
+    if x == 0 || x == 1 {
+        return x;
+    }
+
+    let mut left: i32 = 0;
+    let mut right: i32 = x;
 
     while left <= right {
         let middle = left + (right - left) / 2;
@@ -62,6 +68,8 @@ pub fn my_sqrt3(x: i32) -> i32 {
     right
 }
 
+pub type SolutionFn = fn(i32) -> i32;
+
 fn check_solution(func: SolutionFn) {
     assert_eq!(func(36), 6);
     assert_eq!(func(4), 2);
@@ -76,8 +84,27 @@ fn check_solution(func: SolutionFn) {
 }
 
 fn main() {
-    check_solution(my_sqrt);
+    check_solution(my_sqrt1);
     check_solution(my_sqrt2);
     check_solution(my_sqrt3);
-    println!("END");
+}
+
+#[cfg(test)]
+mod tests {
+    use super::{check_solution, my_sqrt1, my_sqrt2, my_sqrt3};
+
+    #[test]
+    fn test_my_sqrt1() {
+        check_solution(my_sqrt1);
+    }
+
+    #[test]
+    fn test_my_sqrt2() {
+        check_solution(my_sqrt2);
+    }
+
+    #[test]
+    fn test_my_sqrt3() {
+        check_solution(my_sqrt3);
+    }
 }

src/leetcode/0137.single-number-ii/src/main.rs

@@ -2,20 +2,18 @@
 // Use of this source is governed by General Public License that can be
 // found in the LICENSE file.
 
+use std::collections::HashMap;
+
 // map, brute force
+// 使用字典来统计数值出现的次数
 pub fn single_number1(nums: Vec<i32>) -> i32 {
-    use std::collections::HashMap;
-    // 使用字典来统计数值出现的次数
-    let mut count = HashMap::<i32, i32>::new();
-    for num in &nums {
-        count
-            .entry(*num)
-            .and_modify(|value| *value += 1)
-            .or_insert(1);
+    let mut map: HashMap<i32, usize> = HashMap::new();
+    for &num in &nums {
+        map.entry(num).and_modify(|count| *count += 1).or_insert(1);
     }
-    for (key, value) in count {
-        if value == 1 {
-            return key;
+    for (num, count) in map {
+        if count == 1 {
+            return num;
         }
     }
     -1
@@ -37,6 +35,7 @@ pub fn single_number2(nums: Vec<i32>) -> i32 {
     ans
 }
 
+// Bit Manipulation
 pub fn single_number3(nums: Vec<i32>) -> i32 {
     let mut ones = 0;
     let mut twos = 0;

src/leetcode/0287.find-the-duplicate-number/Cargo.toml

@@ -0,0 +1,7 @@
+[package]
+name = "lc-0287-find-the-duplicate-number"
+version = "0.1.0"
+edition = "2021"
+publish = false
+
+[dependencies]

src/leetcode/0287.find-the-duplicate-number/index.md

@@ -0,0 +1,4 @@
+
+# 
+
+[问题描述](../problems/)