1 TLE

#include <bits/stdc++.h>
using namespace std;
int main()
{
    int a, b, c, d;
    cin >> a >> b >> c >> d;
    for (int aa = 0; aa <= 1000; aa++)
        for (int bb = 0; bb <= 1000; bb++)
            for (int cc = 0; cc <= 1000; cc++)
                for (int dd = 0; dd <= 1000; dd++)
                {
                    if (aa + bb + cc + dd == 1000 &&
                        dd % d == 0 &&
                        aa * a + bb * b + cc * c + dd / d == 1000)
                    {
                        cout << aa << " " << bb << " " << cc << " " << dd << "\n";
                        return 0;
                    }
                }
    cout << "-i";
    return 0;
}

2 2997ms

#include <bits/stdc++.h>
using namespace std;
int main()
{
    int a, b, c, d;
    cin >> a >> b >> c >> d;
    for (int aa = 0; aa <= 1000; aa++)
        for (int bb = 0; bb <= 1000; bb++)
            for (int cc = 0; cc <= 1000; cc++)
            {
                int dd = 1000 - aa - bb - cc;
                if (0 <= dd &&
                    dd % d == 0 &&
                    aa * a + bb * b + cc * c + dd / d == 1000)
                {
                    cout << aa << " " << bb << " " << cc << " " << dd << "\n";
                    return 0;
                }
            }
    cout << "-i";
    return 0;
}

3 1289ms

#include <bits/stdc++.h>
using namespace std;
int main()
{
    int a, b, c, d;
    cin >> a >> b >> c >> d;
    for (int aa = 0; aa <= 1000; aa++)
        for (int bb = 0; bb <= 1000 - aa; bb++)
            for (int cc = 0; cc <= 1000 - aa - bb; cc++)
            {
                int dd = 1000 - aa - bb - cc;
                if (dd % d == 0 &&
                    aa * a + bb * b + cc * c + dd / d == 1000)
                {
                    cout << aa << " " << bb << " " << cc << " " << dd << "\n";
                    return 0;
                }
            }
    cout << "-i";
    return 0;
}

4 117ms

#include <bits/stdc++.h>
using namespace std;
int main()
{
    int a, b, c, d;
    cin >> a >> b >> c >> d;
    // 存每种鸡的最大数量(数量限制、钱数限制)
    int maxAA = min(1000, 1000 / a);
    for (int aa = 0; aa <= maxAA; aa++)
    {
        int maxBB = min(1000 - aa, (1000 - aa * a) / b);
        for (int bb = 0; bb <= maxBB; bb++)
        {
            int maxCC = min(1000 - aa - bb, (1000 - aa * a - bb * b) / c);
            for (int cc = 0; cc <= maxCC; cc++)
            {
                int dd = 1000 - aa - bb - cc;
                if (dd % d == 0 &&
                    aa * a + bb * b + cc * c + dd / d == 1000)
                {
                    cout << aa << " " << bb << " " << cc << " " << dd << "\n";
                    return 0;
                }
            }
        }
    }
    cout << "-i";
    return 0;
}