Lotery

lotery.js

var probabilities = [500, 200, 50, 5];
var iterations = 2000;

var results = [];

next:
for (let i = 0; i < iterations; i++) {

	let probability = Math.floor(Math.random() * 1000);
	let j = 0;

	while (j < probabilities.length && probabilities[j] >= probability) {
		j++;

		if (j >= probabilities.length) {
			continue next;
		}
	}

	if (results[j]) {
  	results[j]++;
	} else {
  	results[j] = 1;
  }
}

console.log(results);