function count (number, zeroOrOne) {
    let counter = 0; //броя на 0 или 1
    while (number > 0) {
        let leftover = number % 2;
        if (leftover == zeroOrOne) {
            counter++;
        }

        number = Math.floor(number / 2);
    }

    console.log(counter);
};

count(20, 0);