Reverse words in a string

Problem Statement

Solution 1: Using split, reverse, and join

function reverseWordsUsingSplitReverseJoin(str) {
  return str.split(" ").reverse().join(" ");
} 

const str1 = "Hey Aman is that correct way to reverse words of a string";
reverseWordsUsingSplitReverseJoin(str1);  //output: string a of words reverse to way correct that is Aman Hey 

Solution 2: Using reduce

function reverseWordsUsingReduce(str) {
  return str.split(" ").reduce((reversed, word) => word + " " + reversed, "").trim();
} 

const str1 = "Hey Aman is that correct way to reverse words of a string";
reverseWordsUsingReduce(str1);  //output: string a of words reverse to way correct that is Aman Hey 

Solution 3: Using for loop and push

function reverseWordsUsingForLoopAndPush(str) {
  const words = [];
  let word = "";
  for (let i = 0; i < str.length; i++) {
    if (str[i] === " ") {
      words.push(word);
      word = "";
    } else {
      word += str[i];
    }
  }
  words.push(word);
  return words.reverse().join(" ");
} 

const str1 = "Hey Aman is that correct way to reverse words of a string";
reverseWordsUsingForLoopAndPush(str1);  //output: string a of words reverse to way correct that is Aman Hey 

Solution 4: Using for...of loop

function reverseWordsUsingForOfLoop(str) {
  const words = [];
  let word = "";
  for (const char of str) {
    if (char === " ") {
      words.push(word);
      word = "";
    } else {
      word += char;
    }
  }
  words.push(word);
  return words.reverse().join(" ");
} 

const str1 = "Hey Aman is that correct way to reverse words of a string";
reverseWordsUsingForOfLoop(str1);  //output: string a of words reverse to way correct that is Aman Hey 

Solution 5: Using split and map

function reverseWordsUsingSplitAndMap(str) {
  const words = str.split(" ");
  return words.map((word, index, array) => array[array.length - 1 - index]).join(" ");
} 

const str1 = "Hey Aman is that correct way to reverse words of a string";
reverseWordsUsingSplitAndMap(str1);  //output: string a of words reverse to way correct that is Aman Hey 

Solution 6: Using Array.from and forEach

function reverseWordsUsingArrayFromAndForEach(str) {
  const words = [];
  Array.from(str).forEach((char) => {
    if (char === " ") {
      words.push(words.pop().trim());
      words.push("");
    } else {
      if (words.length === 0) words.push("");
      words[words.length - 1] += char;
    }
  });
  words.push(words.pop().trim());
  return words.reverse().join(" ");
} 

const str1 = "Hey Aman is that correct way to reverse words of a string";
reverseWordsUsingArrayFromAndForEach(str1);  //output: string a of words reverse to way correct that is Aman Hey 

Solution 7: Using String.prototype.replace with a regular expression

function reverseWordsUsingReplaceRegex(str) {
  return str.replace(/(\S+)/g, (match, p1, offset, string) => {
    const words = string.match(/\S+/g);
    return words[words.length - 1 - words.indexOf(p1)];
  });
} 

const str1 = "Hey Aman is that correct way to reverse words of a string";
reverseWordsUsingReplaceRegex(str1);  //output: string a of words reverse to way correct that is Aman Hey 

Solution 8: Using split, filter, and reduce

function reverseWordsUsingSplitFilterReduce(str) {
  return str.split(" ")
            .filter(word => word.length > 0)
            .reduce((reversed, word) => word + " " + reversed, "")
            .trim();
} 

const str1 = "Hey Aman is that correct way to reverse words of a string";
reverseWordsUsingSplitFilterReduce(str1);  //output: string a of words reverse to way correct that is Aman Hey 

Solution 9: Using a stack data structure

function reverseWordsUsingStack(str) {
  const stack = [];
  let word = "";
  for (let i = 0; i < str.length; i++) {
    if (str[i] === " ") {
      stack.push(word);
      word = "";
    } else {
      word += str[i];
    }
  }
  stack.push(word);
  return stack.reverse().join(" ");
} 

const str1 = "Hey Aman is that correct way to reverse words of a string";
reverseWordsUsingStack(str1);  //output: string a of words reverse to way correct that is Aman Hey 

Solution 10: Using split, sort, and join with index manipulation

function reverseWordsUsingSplitSortJoin(str) {
  const words = str.split(" ");
  return words.sort((a, b) => words.length - words.indexOf(a) - (words.length - words.indexOf(b))).join(" ");
} 

const str1 = "Hey Aman is that correct way to reverse words of a string";
reverseWordsUsingSplitSortJoin(str1);  //output: string a of words reverse to way correct that is Aman Hey