Least common multiple

Least common multipleWikipedia

Factors and multiples | Pre-algebra | Math | Khan AcademyKhan Academy

JavaScript

const primeFactorization = (x) => {
  const map = new Map();
  let divisor = 2;
  
  while (divisor <= x) {
    if (x % divisor === 0) {
      map.set(divisor, (map.get(divisor) || 0) + 1);
      x /= divisor;
    } else {
      divisor += 1;
    }
  }
  
  return map;
};

const leastCommonMultiple = (a, b) => {
  const factors = new Map();
  primeFactorization(a).forEach((v, key) => factors.set(key, factors.get(key) > v ? factors.get(key) : v));
  primeFactorization(b).forEach((v, key) => factors.set(key, factors.get(key) > v ? factors.get(key) : v));
  
  return [...factors.entries()].reduce((acc, cur) => acc * (cur[0] ** cur[1]), 1);
};