repeat the chars

day2_repeat_chars.py

@@ -0,0 +1,16 @@
+# Required concepts: https://www.w3schools.com/python/python_intro.asp Everything till for loops
+
+print('Question: repeat every character twice')
+
+li = ['a' , 'b' , 'c' , 'd']
+# we want ['aa' , 'bb' , 'cc' , 'dd']
+
+for i in range(len(li)):
+  li[i]  = li[i]*2
+  # all elements repeat twice so *2
+
+#single line let's repeat them again
+result = [letter*2 for letter in li]
+print('Answer:')
+print(result)
+

day2_reverse_halves.py

@@ -0,0 +1,19 @@
+# Required concepts: https://www.w3schools.com/python/python_intro.asp Everything till for loops
+
+print('Question: return reverse first half of l1 and reverse of second half of l2')
+
+l1 = ['a' , 'b' , 'c' , 'd']
+l2 = ['e' , 'f' , 'g' , 'h']
+
+# reverse first half of l1 and second of l2
+# we want: ['b' , 'a' , 'h' , 'g']
+
+# cut the first list into first half reverse and second into second half reverse
+half1 = len(l1)//2 - 1
+half2 = len(l2)//2 - 1
+# -1 for 0 based indicing
+result =  l1[half1::-1] + l2[:half2:-1]
+
+print('Answer:')
+print(result)
+

main.py

@@ -1,19 +1,16 @@
 # Required concepts: https://www.w3schools.com/python/python_intro.asp Everything till for loops
 
-print('Question: count occurance of 2 in a number')
+print('Question: repeat every character twice')
 
-number = '222222222223456'
-count = 0
+li = ['a' , 'b' , 'c' , 'd']
+# we want ['aa' , 'bb' , 'cc' , 'dd']
 
-# go through all the digits, check if it is 2
-for digit in number:
-  if digit == '2':
-    count += 1
-
-# single line
-count = len(number) - len(number.replace('2',''))
+for i in range(len(li)):
+  li[i]  = li[i]*2
+  # all elements repeat twice so *2
 
+#single line let's repeat them again
+result = [letter*2 for letter in li]
 print('Answer:')
-print('2 has ',count,'occurances')
+print(result)
 
-#If you are same as your reverse, you are a palindrome