[JS] Factorial 구현

1. 반복문

/**
 * @param {number} number
 * @return {number}
 */
const factorial = (number) => {
  let result = 1;

  for (let i = 2; i <= number; i += 1) {
    result *= i;
  }

  return result;
}

2. 재귀

/**
 * @param {number} number
 * @return {number}
 */
const factorialRecursive = (number) => {
  return number > 1 ? number * factorialRecursive(number - 1) : 1;
}

https://github.com/trekhleb/javascript-algorithms/tree/master/src/algorithms/math/factorial