generate random numbers

random.js

function getRandom(cb) {
  var now = new Date().getTime() - (Math.random(10)*1000);
  setTimeout(function() {
    var then = new Date().getTime() * 1000;
    cb((then-now)/Math.random(100));
  }, Math.random(90));
}
var randomSet = {}
var collisionCount = 0;
var count = 0;
var trials = 100001;
for (var i = 0; i < trials; ++i) {
  getRandom(function(rn) {
    console.log(rn);
    ++count;
    if (randomSet[rn]) {
      ++collisionCount;
    }
    randomSet[rn] = 1;
    if (count % 1000 == 0 || count == trials) {
      console.log("processed: " + count + " with: " + collisionCount + " collisions");
    }
  });
}