Java 统计整数二进制中1的个数

package cookie;

public class CountBinary_1 {

    public static void main(String[] args) {
        System.out.println(count(12));
    }

    // n为自然数
    public static int count(int n) {
        int count = 0;
        while (n > 0) {
            count++;
            n = n & (n - 1);
        }
        return count;
    }
}

参考《剑指offer》78页