select random value NOT in array

Question

How would I select a random value (0 to 30) that is not in this array?

var list = new Array(1,3,4,7,8,9);

Answer 1

A little recursive function:

getNum() {
  let randomNum = Math.floor(Math.random() * (30 - 1)) + 1
  if (list.includes(randomNum)) {
    return getNum()
  }
   return randomNum
}

Might be a little faster, since it first tries to return a random number, and then checks if it's in the array.