30秒学会 JavaScript 片段 · 2018年1月15日

30秒学会 JavaScript 片段 – lcm

Returns the least common multiple of two or more numbers.

Use the greatest common divisor (GCD) formula and the fact that lcm(x,y) = x * y / gcd(x,y) to determine the least common multiple.
The GCD formula uses recursion.

代码片段

const lcm = (...arr) => {
  const gcd = (x, y) => (!y ? x : gcd(y, x % y));
  const _lcm = (x, y) => (x * y) / gcd(x, y);
  return [...arr].reduce((a, b) => _lcm(a, b));
};

使用样例

lcm(12, 7); // 84
lcm(...[1, 3, 4, 5]); // 60