factorial function in JS two ways

factorial-javascript.js

function factorial (n) {
  let product = 1
  for (let i=n; i>0; i--) {
    product = product * i
  }
  return product
}

console.log(factorial(5))

function factorialRecursion (n) {
  if (n===0) {
    return 1
  } else {
    return n * factorialRecursion(n-1)
  }
}

console.log(factorialRecursion(5))