Reverse String -LeetCode

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"]

Java Solution :

class Solution {
    public void reverseString(char[] s) {
        if(s.length == 0 || s == null)
            return;
        int k = s.length;
        for(int i =0 ; i < k/2;i++){
            char temp = s[i];
            s[i] = s[k-i-1];
            s[k-i-1] = temp;
        }
    }
}