Get number of words in an array starting with certain characters

SarahCodes 0
Viewed 29

I'm trying to solve a problem on a testing website and I'm getting confused on trying to find a way to match the letters of a passed in array wordlist.

In the below example it should be returning 2, as ye should be matched twice - in yesterday and yellow.

Without using a RegEx what would be the best way be to go about getting a passed in wordlist to return a number amount based on the 2nd argument input?

This is the code I have so far, that isn't working:

let wordList = ['yesterday', 'develop', 'environment', 'yellow', 'yikes', 'envious']

const countingLetters = (words, inputStart) => {
  let total = 0;
  for (let i = 0; i < words.length; i++) {
    if (inputStart == words[i]) {
      total += 1;
    }
  }
  return total;
};


console.log(countingLetters(wordList, 'ye'));

function arrays javascript
1 Answers

To do what you require without a regex, you can use the filter() function, to search the array by a given condition, and the indexOf() method to ensure that the match is at the start of the string:

let wordList = ['yesterday', 'develop', 'environment', 'yellow', 'yikes', 'envious']

const countingLetters = (words, inputStart) => 
  words.filter(word => word.indexOf(inputStart) === 0).length;

console.log(countingLetters(wordList, 'ye'));

Rory McCrossan0
Related