题解

#include <iostream>
#include <cstdio>
using namespace std;

int main() {
    int n;
    cin >> n;
    for (int i = 0; i * i <= n; i++) {
        int res = n - i * i;
        for (int j = 0; j * j <= res; j++) {
            int res2 = res - j * j;
            for (int k = 0; k * k <= res2; k++) {
                int res3 = res2 - k * k;
                for (int p = 0; p * p <= res3; p++) if (i * i + j * j + k * k + p * p == n) {
                    printf("%d %d %d %d", i, j, k, p);
                    return 0;
                }
            }
        }
    }
    return 0;
}