Iterate over a String.
For loop version:
str = 'Python'
for letter in str:
print letter
While loop version:
str = 'Python'
i = 0
while i < len(str):
print str[i]
i = i+1
In the for-loop we don’t need the index variable to iterate over the string, while in the while loop we use the variable i as the index for the string. We first initialize the variable i and set it to 0. Then, every time when the loop is executed, the variable i is increased by 1 until it reaches the last index.
