#include <cstdio>
#include <cstring>
#include <algorithm>
#define ll long long
int T;
ll n, m, x1, x2, ans;
int main()
{
    scanf("%d", &T);
    while(T--)
    {
        scanf("%lld%lld%lld%lld", &n, &m, &x1, &x2);
        ans=n-1;
        ans=std::min(ans, x1-1);
        ans=std::min(ans, m-x2);
        ans=std::min(ans, (std::max(0ll, std::abs(x1-x2)-1)+n-2+1)/2);
        ans=std::max(ans, 0ll);
        printf("%lld\n", ans*ans);
    }
    return 0;
}