样例全过，但0pts求助

#include<bits/stdc++.h>
using namespace std;
#define int long long
int f[25][25][25], a, b, c;
int w(int a, int b, int c) {
    if(a <= 0 || b <= 0 || c <= 0) return 1;
    if(a > 20 || b > 20 || c > 20) return w(20, 20, 20);
    if(f[a][b][c] != 0) return f[a][b][c];
    if(a < b && b < c) {
        return f[a][b][c] = w(a, b, c - 1) + w(a, b - 1, c - 1) - w(a, b - 1, c);
    }
    else {
        return f[a][b][c] = w(a - 1, b, c) + w(a - 1, b - 1, c) + w(a - 1, b, c - 1) - w(a - 1, b - 1, c - 1);
    }
}
signed main() {
    while(cin >> a >> b >> c) {
        if(a == -1 && b == -1 && c == -1) {
            return 0;
        }
        cout << "w(" << a << "," << b << "," << c << ") = " << w(a, b, c) << endl;
    }
    return 0;
}