// your code goes here
function hitungNomorBit(angka, nomorBit) {
	//validasi
	if (nomorBit !== 0 && nomorBit !== 1) {
		return null;
	}
 
	// konversi biner
	var biner = [];
	var n = angka;
 
	if(n === 0) {
		biner.push(0);
	} else {
		while (n > 0) {
			var sisa = n % 2;
			biner.unshift(sisa);
			n = Math.floor(n/2);
		}
	}
 
	//hitung jumlah bit
	var jumlah = 0;
	for (var i = 0; i < biner.length; i++) {
		if (biner[i] === nomorBit){
			jumlah++;
		}
	}
 
	return jumlah;
}
 
print(hitungNomorBit(13, 0));
print(hitungNomorBit(13, 1));
print(hitungNomorBit(13, 2));

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