Count How Often Each Word Appears in JavaScript (Exercise)

The challenge

Write wordCount(text) that returns an object with each word (in lowercase) and how many times it appears. Words are separated by spaces.

Example

wordCount("the cat and the hat")
// { the: 2, cat: 1, and: 1, hat: 1 }

Try it

Write your answer below, then press Check my answer. Your code runs right here in your browser, and the tests tell you what works.

Your solution

It prints

What the tests check

wordCount("the cat and the hat") gives { the: 2, cat: 1, and: 1, hat: 1 }
wordCount("Go go GO") gives { go: 3 }
wordCount("hi") gives { hi: 1 }

Hints

Stuck? Open one hint at a time. Try again after each one.

Hint 1

Start with const counts = {}; and loop over text.toLowerCase().split(" ").

Hint 2

counts[word] = (counts[word] || 0) + 1;

A solution

There’s always more than one right way. Read it, make sure you understand it, then try writing it yourself without looking.

Show one possible solution

Solution

function wordCount(text) {
  const counts = {};
  for (const word of text.toLowerCase().split(" ")) {
    counts[word] = (counts[word] || 0) + 1;
  }
  return counts;
}

Learn what you need

This exercise uses what Grade 8: Objects: Describing Things With Labels teaches. Read those notes first if any of it is new.

Count how often each word appears