Simple Find Closest Word

closest-word.js

// You can modify these
const wordsToCheck = ["Apple", "red  delisous", "orangg", "rgapefruit"];
const dictionary = ["apple", "banana", "orange", "grapefruit", "red delicious"];

// Don't modify below here
const ALPHABET = "qwertyuiopasdfghjklzxcvbnm1234567890_ ".split("").sort();

const BASE_ALPHABET_HASH = ALPHABET.reduce((acc, x) => ({[x]: 0, ...acc}), {});

const DICTIONARY_HASHES = dictionary.map((w) => buildFreqHash(cleanStr(w)));

// clean a string
function cleanStr(s) {
  return s.replace(/[\s_]+/g, " ").toLowerCase();
}

const distance = (a, b) => a.reduce((acc, v, i) => acc + Math.abs(v - b[i]), 0);

// build a character frequency hash from a string in alphabetical order
function buildFreqHash(s) {
  const h = {...BASE_ALPHABET_HASH};
  s.split("").forEach((l) => h[l]++);
  return ALPHABET.map((l) => h[l]);
}

// find the closest word based on the fewest edits
function closestWord(word) {
  const hash = buildFreqHash(cleanStr(word));
  const distances = DICTIONARY_HASHES.map((h) => distance(hash, h));
  return dictionary[
    distances.reduce(
      (closestIdx, d, i) => (distances[closestIdx] < d ? closestIdx : i),
      0
    )
  ];
}

// This runs the code
wordsToCheck.forEach((w) =>
  console.log(`'${closestWord(w)}' is closest to '${w}'`)
);

/**
 * Output:
 * 'apple' is closest to 'Apple'
 * 'red delicious' is closest to 'red  delisous'
 * 'orange' is closest to 'orangg'
 * 'grapefruit' is closest to 'rgapefruit'
 */