ユークリッド互除法 #js

gcd.js

// https://blog.ver001.com/javascript-aspect-ratio/
const getGCD = (a, b) => (b === 0 ? a : getGCD(b, a % b));
const getAspectRatio = (w, h) => {
  const gcd = getGCD(w, h);
  return `${w / gcd}:${h / gcd}`;
};