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What’s your alternative solution? Challenge #54

About this series

This is series of daily JavaScript coding challenges... for both beginners and advanced users.

Each day I’m gone present you a very simple coding challenge, together with the solution. The solution is intentionally written in a didactic way using classic JavaScript syntax in order to be accessible to coders of all levels.

Solutions are designed with increase level of complexity.

Today’s coding challenge

Create a function to return the longest word(s) in a string

(scroll down for solution)

Code newbies

If you are a code newbie, try to work on the solution on your own. After you finish it, or if you need help, please consult the provided solution.

Advanced developers

Please provide alternative solutions in the comments below.

You can solve it using functional concepts or solve it using a different algorithm... or just solve it using the latest ES innovations.

By providing a new solution you can show code newbies different ways to solve the same problem.


// Solution for challenge48

var text = "Create a function to return the longest word(s) in a sentance.";


function getLongestWords(text)
    var words = getWords(text);

    var maxSize = 0;
    var maxPositions = [];

    for(var i = 0; i < words.length; i++)
        var currWordSize = words[i].length;

        if (currWordSize > maxSize)
            maxSize = currWordSize;
            maxPositions = [ i ];
        else if (currWordSize === maxSize)

    return getElements(words, maxPositions);

// Get only the elements from specified positions from the array
function getElements(ar, arPositions)
    var arNew = [];

    for(var pos of arPositions)

    return arNew;

// Returns an array with the words from specified text
function getWords(text)
    let startWord = -1;
    let ar = [];

    for(let i = 0; i <= text.length; i++)
        let c = i < text.length ? text[i] : " ";

        if (!isSeparator(c) && startWord < 0)
            startWord = i;

        if (isSeparator(c) && startWord >= 0)
            let word = text.substring(startWord, i);

            startWord = -1;

    return ar;

function isSeparator(c)
    var separators = [" ", "\t", "\n", "\r", ",", ";", ".", "!", "?", "(", ")"];
    return separators.includes(c);

To quickly verify this solution, copy the code above in this coding editor and press "Run".

Note: The solution was originally designed for environment, and therefore is making use of println. This is the almost equivalent of console.log in other environments. Please feel free to use your preferred coding playground / environment when implementing your solution.

Top comments (3)

rafaacioly profile image
Rafael Acioly

Python solution 🐍

def longest_word(text: str) -> int:
  return max([
    len(word) for word in text.split()
    if not word.isspace()

content = "Create a function to return the longest word(s) in a sentance."
print(longest_word(content))  # 9
jpantunes profile image
JP Antunes • Edited

Using a few 'modern' ES5+ constructs, we can reduce the solution to four lines of code.

Annotated version:

const longestWord = input => {
    //remove any character that isn't alphabetic (\w) or a blank space (\s) from input 
    //and split the resulting string on blank spaces, ie: this -> 'two word(s)!' becomes -> ['two', 'words']
    const words = input.replace(/[^\w\s]/g,'').split(' ');
    let maxLen = 0;
    //iterate over words to find the size of the longest word by comparing each length to the previous maxLen
    for (const word of words) maxLen = Math.max(maxLen, word.length);
    //return all words whose length is maxLen
    return words.filter(e => e.length == maxLen);
trasherdk profile image

This could probably be reduced even more:

const text = "Create a function to return the longest word(s) in a sentance.";

let result = text.replace(/[^a-zA-Z ]/g,'').split(' ').sort((a,b) => {
    return a.length - b.length;
} )

let longest = result[result.length-1].length
result = result.filter( (a) => {
  return a.length >= longest