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

int main(){
    int tt;scanf("%d",&tt);
    for (;tt--;){
        int n,m,x,y;scanf("%d%d%d%d",&n,&m,&x,&y);
        int ans=n-1;
        if (x==y)
            ans=min(ans, (n-1)/2);
        else ans=min(ans, (abs(x-y)+n-1-1)/2);
        ans=min(ans, x-1);
        ans=min(ans, m-y);
        
        ans=max(ans,0);
        cout<<1ll*ans*ans<<endl;
    }
}