ReverseWordsInAString.js

// Source : https://oj.leetcode.com/problems/reverse-words-in-a-string/
// Author : Dean Shi
// Date   : 2015-06-13

/**********************************************************************************
 *
 * Given an input string, reverse the string word by word.
 *
 * For example,
 * Given s = "the sky is blue",
 * return "blue is sky the".
 *
 *
 * Clarification:
 *
 * What constitutes a word?
 * A sequence of non-space characters constitutes a word.
 * Could the input string contain leading or trailing spaces?
 * Yes. However, your reversed string should not contain leading or trailing spaces.
 * How about multiple spaces between two words?
 * Reduce them to a single space in the reversed string.
 *
 *
 **********************************************************************************/

/**
 * @param {string} str
 * @returns {string}
 */
var reverseWords = function(str) {
    return str.trim().split(/ +/).reverse().join(' ')
};

// Test case
console.log(reverseWords('the sky is blue') === 'blue is sky the'); // true