#include<cstdio>
#include<cmath>
#include<algorithm>
using namespace std;
int t,n,m,x1,x2;
int main()
{
    scanf("%d",&t);
    while(t--)
    {
        scanf("%d%d%d%d",&n,&m,&x1,&x2);
        int Minn=min(min(x1-1,m-x2),n-1);
        if(x1==x2) Minn=min(Minn,(n-1)/2);
        else Minn=min(Minn,(abs(x2-x1)+n-2)/2);
        printf("%lld\n",(long long)Minn*Minn);
    }
}