leetcode 344. Reverse String

Seawolf

Write a function that reverses a string. The input string is given as an array of characters char[].

Do not allocate extra space for another array, you must do this by modifying the input array in-place with O(1) extra memory.

You may assume all the characters consist of printable ascii characters.

 

Example 1:

Input: ["h","e","l","l","o"]
Output: ["o","l","l","e","h"]
Example 2:

Input: ["H","a","n","n","a","h"]
Output: ["h","a","n","n","a","H"]

class Solution {
    public void reverseString(char[] s) {
        int i = 0;
        while(s.length -1 - i - i >=1 && i < s.length - 1){
            
            char temp = s[i];
            s[i] = s[s.length - 1 - i];
            s[s.length - 1-i] = temp;
            i++;
        }
    }
}