leetcode 344 翻转字符串

就这？

class Solution {
public:
    void reverseString(vector<char>& s) 
    {
        int n = s.size();
        int i = 0;
        int j = n-1;
        while(i<j)
        {
            swap(s[i++],s[j--]);
        }         
    }
};