【leetcode 简单】 第八十二题 反转字符串

class Solution:
    def reverseString(self, s):
        """
        :type s: str
        :rtype: str
        """
        #return s[::-1]
        start = 0
        end = len(s)-1
        tmp=[i for i in s]
        while start < end:
            tmp[start],tmp[end] = tmp[end],tmp[start]
            start+=1
            end-=1
        return ‘‘.join(tmp)