[LeetCode]344. Reverse String(反转字符串)

344. Reverse String

Write a function that takes a string as input and returns the string reversed.
题目大意：反向输出字符串

• Example:

  Given s = "hello", return "olleh".
  

代码如下

C++

class Solution {
public:
    string reverseString(string s) {
        int a = s.size()-1;
        string b = "";
        for(int i=a;i>=0;i--)
            b += s[i];
        return b;
    }
};

注意：设置a是为了不用每次循环都执行s.size()-1