LeetCode541字符串翻转2

# coding:utf-8
"""
Name : NO541.py
Author  : qlb
Contect : 17801044486@163.com
Time    : 2021/2/7 9:28
Desc: 翻转字符串2
"""
#解题思路
# 把遍历的步长改为 2*k 即可 将 i:i + k 这段字符串进行翻转
class Solution:
    def reverseStr(self, s: str, k: int) -> str:
        s = list(s)
        for i in range(0, len(s), 2 * k):
            s[i:i + k] = self.myReverse(s[i:i + k])
        return ''.join(s)

    def myReverse(self, s):
        i = 0
        j = len(s) - 1
        while i < j:
            tmp = s[j]
            s[j] = s[i]
            s[i] = tmp
            i += 1
            j -= 1
        return s