leetcode 344. Reverse String

Write a function that takes a string as input and returns the string reversed.

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

class Solution(object):
    def reverseString(self, s):
        """
        :type s: str
        :rtype: str
        """
        return s[::-1]

其他解法：

public class Solution {
    public String reverseString(String s) {
        byte[] bytes = s.getBytes();
        int i = 0;
        int j = s.length() - 1;
        while (i < j) {
            bytes[i] = (byte) (bytes[i] ^ bytes[j]);
            bytes[j] = (byte) (bytes[i] ^ bytes[j]);
            bytes[i] = (byte) (bytes[i] ^ bytes[j]);
            i++;
            j--;
        }
        return new String(bytes);
    }
}

用到了交换不用任何空间。

public class Solution {
    public String reverseString(String s) {
        byte[] bytes = s.getBytes();
        int i = 0;
        int j = s.length() - 1;
        while (i < j) {
            byte temp = bytes[i];
            bytes[i] = bytes[j];
            bytes[j] = temp;
            i++;
            j--;
        }
        return new String(bytes);
    }
}

class Solution {
public:
    string reverseString(string s) {
        int i = 0, j = s.size() - 1;
        while(i < j){
            swap(s[i++], s[j--]); 
        }
        
        return s;
    }
};