58. Length of Last Word

Given a string s consists of upper/lower-case alphabets and empty space characters ' ', return the length of last word in the string.

If the last word does not exist, return 0.

Note: A word is defined as a character sequence consists of non-space characters only.

Example:

Input: "Hello World"
Output: 5

Runtime: 52 ms, faster than 81.86% of JavaScript online submissions for Length of Last Word.

/**
 * @param {string} s
 * @return {number}
 */
var lengthOfLastWord = function(s) {
    const words = s.trim().split(' ');
    return words[words.length - 1].length;
};

Runtime: 52 ms, faster than 81.86% of JavaScript online submissions for Length of Last Word.

/**
 * @param {string} s
 * @return {number}
 */
var lengthOfLastWord = function(s) {
    const words = s.match(/\w+/g);
    return words ? words[words.length - 1].length : 0;
};

Runtime: 48 ms, faster than 100.00% of JavaScript online submissions for Length of Last Word.

/**
 * @param {string} s
 * @return {number}
 */
var lengthOfLastWord = function(s) {
    if (s.length < 1) {
        return 0;
    }
    let count = 0;
    for (let i = s.length - 1; i >= 0; i--) {
        if (s[i] === ' ') {
            if (count < 1) {
                continue;
            } else {
                return count;
            }
        }
        count++;
    }
    return count;
};