C++ 代码

#include <iostream>
using namespace std;

int main()
{
    int N;
    cin >> N;
    int ret = 0;
    int a[4] = {64, 16, 4, 1};
    N = 1024 - N;
    for(int i = 0; i < 4; ++ i){
        int cnt = N / a[i];
        N -= cnt * a[i];
        ret += cnt;
    }
    cout << ret << endl;

    return 0;
}