#include <bits/stdc++.h>
using namespace std;

void work() {
    int A, B, C, D;
    cin >> A >> B >> C >> D;
    if (A < 4) cout << "0\n";
    else {
        int ans = 4;
        for (int i = 3; i <= 9; i += 2) {
            for (int j = 3; ; j += 2) {
                int a = 4;
                int b = (i - 3 + j - 3) + 2;
                int c = (i - 3 + j - 3) + 2;
                int d = (i - 2) * (j - 2);
                assert (a + b + c + d == i * j);
                if (a <= A && b <= B && c <= C && d <= D) {
                    ans = max(ans, i * j);
                } else break;
            }
        }
        for (int i = 2; i <= 10; i += 2) {
            for (int j = 2; ; j += 2) {
                int a = 4;
                int b = (i - 2 + j - 2);
                int c = (i - 2 + j - 2);
                int d = (i - 2) * (j - 2);
                assert (a + b + c + d == i * j);
                if (a <= A && b <= B && c <= C && d <= D) {
                    ans = max(ans, i * j);
                } else break;
            }
        }
        cout << ans << '\n';
    }
}

int main() {
    int T; cin >> T;
    while (T--) work();
}