leetcode/work/Easy/Two Pointers/344.reverse-string.js

/*
 * 344. Reverse String
 * Difficulty: Easy
 * https://leetcode.com/problems/reverse-string/
 * 
 * ──────────────────────────────────────────────────
 * 
 * Write a function that reverses a string. The input string is given as
 * an array of characters s.
 * 
 * You must do this by modifying the input array in-place with O(1)
 * extra memory.
 * 
 *  
 * 
 * Example 1:
 * 
 * Input: s = ["h","e","l","l","o"]
 * Output: ["o","l","l","e","h"]
 * 
 * Example 2:
 * 
 * Input: s = ["H","a","n","n","a","h"]
 * Output: ["h","a","n","n","a","H"]
 * 
 *  
 * 
 * Constraints:
 * 
 * 	• 1 <= s.length <= 10^5
 * 
 * 	• s[i] is a printable ascii character.
*/

/**
 * @param {character[]} s
 * @return {void} Do not return anything, modify s in-place instead.
 */
var reverseString = function(s) {

    let i = 0;
    let j = s.length - 1;
    
    while (i < j) {
        [s[i], s[j]] = [s[j], s[i]];
        j--;
        i++;
    }
};