var arr var counts for var arr length counts arra var sorted for var c

var arr = [5, 4, 2, 1, 1, 2, 3]
var counts = [0, 0, 0, 0, 0, 0, 0];

for (var i = 0; i < arr.length; i++) {
	counts[arra[i]]++;
}

var sorted = [];
for (var i = 0; i < counts.length; i++) {
	for (var j = 0; j < counts[i]; j++) {
		sorted.push(i);
	}
}