Javascript random on array without repeat [duplicate]

Answer 1

Just shuffle the question array and pick one after the other. In a simplified version:

var questions = [1,2,3,4,5,6,7,8,9,10];

function shuffle(a) {
  var cidx, ridx,tmp;
  cidx = a.length;
  while (cidx != 0) {
    ridx = Math.floor(Math.random() * cidx);
    cidx--;
    tmp = a[cidx];
    a[cidx] = a[ridx];
    a[ridx] = tmp;
  }
  return a;
}

function* get_one(arr){
  var idx = arr.length;
  while(idx != 0)
    yield arr[idx--];
}

questions = shuffle(questions);
console.log(questions);

var nextq = get_one(questions);
var alen = questions.length -1;
while(alen--)
  console.log(nextq.next().value);

You don't need that fancy generator, you can just get one after the other in a simple loop if you prefer that.