Factorialize a Number

bonfire-factorialize-a-number.js

// Bonfire: Factorialize a Number
// Author: @joepichardo
// Challenge: http://www.freecodecamp.com/challenges/bonfire-factorialize-a-number
// Learn to Code at Free Code Camp (www.freecodecamp.com)

function factorialize(num) {
  if(num === 0){
    return 1;
  }
  
  var newNum = num; //make new variable so there is no infinite for loop
  
  //for loop starts at 1 and multiplies until it reaches num
  for(var i = 1; i < num; i++){
    newNum = newNum * i;
  }
  num = newNum;
  
  return num;
}

factorialize(5);