#include<bits/stdc++.h>
#define debug(x) cerr<<"\tDEBUG: "<<#x<<" = "<<(x)<<endl
using namespace std;
const int maxn=12,P=998244353;

int main(){
//    freopen("data.in","r",stdin);
//    freopen("std.out","w",stdout);
    int QuQ;cin>>QuQ;
    while(QuQ--){
        int n,m,x1,x2;
        scanf("%d%d%d%d",&n,&m,&x1,&x2);
        if(n==1||m==1){
            puts("0");
            continue;
        }
        int ans=min(x1-1,m-x2);
        ans=min(ans,n-1);
        int tmp1=n-1;
        int tmp2=abs(x1-x2);
        
        if(tmp1>tmp2)swap(tmp1,tmp2);
        
        if(tmp1!=0){
            
            if(tmp1%2==tmp2%2){
                tmp2--;
            }
            ans=min(ans,(tmp1+tmp2)/2);
            
        }else {
            ans=min(ans,tmp2/2);
        }
        cout<<1LL*ans*ans<<endl;
    }
    
    return 0;
}