100分但#2WA且已开longlong

#include<iostream>
using namespace std;

long long store[30][30][30]{0};
long long result[100000]{};
long long hh[100000][3]{};
long long a = 0, b = 0, c = 0;
int times = 0;

long long w(long long a, long long b, long long c) {
    if ((a <= 0) || (b <= 0) || (c <= 0)) {
        return 1;
    }
    if ((a > 20) || (b > 20) || (c > 20)) {
        return w(20, 20, 20);
    }
    if (store[a][b][c] > 0) {
        return store[a][b][c];
    }
    if ((a < b) && (b < c)) {
        store[a][b][c] = w(a, b, c - 1) + w(a, b - 1, c - 1) - w(a, b - 1, c);
        return store[a][b][c];
    }
    store[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);
    return store[a][b][c];
}

int main() {

    for (int i = 0; (a != -1) || (b != -1) || (c != -1); i++) {
        cin >> a >> b >> c;
        result[i] = w(a, b, c);
        hh[i][0] = a;
        hh[i][1] = b;
        hh[i][2] = c;
        times++;
    }

    for (int i = 0; i < times - 1; i++) {
        cout << "w(" << hh[i][0] << ", " << hh[i][1] << ", " << hh[i][2] << ") = " << result[i] << endl;
    }

    return 0;
}

在自己电脑上运行与期望输出值一致，但在洛谷平台提交后显示我该测试点的计算结果变为负值。