PF - Basic Syntax - Exercise - 08. Mutate Strings

first_word = input()
second_word = input()

mutate_word = ''

for i in range(len(first_word)):
    mutate_word = second_word[:i+1] + first_word[i+1:]
    if mutate_word != first_word:
        first_word = mutate_word
        print(first_word)