Problem-Solving-with-Algorithms-and-Data-Structures-using-Python/recursion/reverse-string.py at master · ivanmmarkovic/Problem-Solving-with-Algorithms-and-Data-Structures-using-Python · GitHub

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string: str = "This string will be reversed"


def reverse_string(string: str) -> str:

    def helper(s: str, end: int) -> str:
        if end < 0:
            return ""
        else:
            return s[end] + helper(s, end - 1)

    return helper(string, len(string) - 1)


print(reverse_string(string))


def reverse_string_ex_one(string: str) -> str:
    if len(string) == 0:
        return ""
    else:
        return reverse_string_ex_one(string[1:]) + string[0]


print(reverse_string_ex_one(string))


def reverse_string_ex_two(string: str) -> str:
    if len(string) == 0:
        return ""
    else:
        return string[len(string) - 1] + reverse_string_ex_two(string[0: len(string) - 1])


print(reverse_string_ex_two(string))