reverse_string.py

"""
344. 反转字符串
递归 双指针 字符串
简单


编写一个函数，其作用是将输入的字符串反转过来。输入字符串以字符数组 char[] 的形式给出。

不要给另外的数组分配额外的空间，你必须原地修改输入数组、使用 O(1) 的额外空间解决这一问题。

你可以假设数组中的所有字符都是 ASCII 码表中的可打印字符。

 

示例 1：

输入：["h","e","l","l","o"]
输出：["o","l","l","e","h"]
示例 2：

输入：["H","a","n","n","a","h"]
输出：["h","a","n","n","a","H"]

来源：力扣（LeetCode）
链接：https://leetcode-cn.com/problems/reverse-string
"""
from typing import List


class Solution:
    def reverseString(self, s: List[str]) -> None:
        """
        Do not return anything, modify s in-place instead.
        """
        left = 0
        right = len(s) - 1
        while left < right:
            s[left], s[right] = s[right], s[left]
            left += 1
            right -= 1


if __name__ == '__main__':
    solution = Solution()

    result = ["h", "e", "l", "l", "o"]
    solution.reverseString(result)
    print(result)
    assert result == ["o", "l", "l", "e", "h"]

    result = ["H", "a", "n", "n", "a", "h"]
    solution.reverseString(result)
    print(result)
    assert result == ["h", "a", "n", "n", "a", "H"]