public class jinzhi {
    public static void main(String[] args) {
        int a = 15;
        int n = 0;
        int i=0;
        while (a > 0) {
            n = (int) (n + (a % 2) * Math.pow(10,i));
            a = a / 2;
            i=i+1;
        }
        System.out.print("十进制a转换二进制n为：" + n);
    }
}