Find anagrams using the fundamental theorem of arithmetic.

prime_anagram.js

// Find anagrams using the fundamental theorem of arithmetic. Not at all
// efficient and stops working very quickly due to floating point imprecision.
// Inspired by https://twitter.com/fermatslibrary/status/988399621402656773

const primes = {
  "a": 2,
  "b": 3,
  "c": 5,
  "d": 7,
  "e": 11,
  "f": 13,
  "g": 17,
  "h": 19,
  "i": 23,
  "j": 29,
  "k": 31,
  "l": 37,
  "m": 41,
  "n": 43,
  "o": 47,
  "p": 53,
  "q": 59,
  "r": 61,
  "s": 67,
  "t": 71,
  "u": 73,
  "v": 79,
  "w": 83,
  "x": 89,
  "y": 97,
  "z": 101,
};

const getPrimeProduct = s => s
  .toLowerCase()
  .replace(/\s/g, "")
  .split("")
  .map(c => primes[c])
  .reduce((val, acc) => val * acc);

const isAnagram = (a, b) => getPrimeProduct(a) === getPrimeProduct(b);

console.log(isAnagram("are", "ear"));