#include<bits/stdc++.h>
typedef long long ll;
ll gi(){
    ll x=0,f=1;
    char ch=getchar();
    while(!isdigit(ch))f^=ch=='-',ch=getchar();
    while(isdigit(ch))x=x*10+ch-'0',ch=getchar();
    return f?x:-x;
}
std::mt19937 rnd(time(NULL));
#define rand rnd
#define pr std::pair<int,int>
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
template<class T>void cxk(T&a,T b){a=a>b?a:b;}
template<class T>void cnk(T&a,T b){a=a<b?a:b;}
#ifdef mod
int pow(int x,int y){
    int ret=1;
    while(y){
        if(y&1)ret=1ll*ret*x%mod;
        x=1ll*x*x%mod;y>>=1;
    }
    return ret;
}
template<class Ta,class Tb>void inc(Ta&a,Tb b){a=a+b>=mod?a+b-mod:a+b;}
template<class Ta,class Tb>void dec(Ta&a,Tb b){a=a>=b?a-b:a+mod-b;}
#endif
int main(){
#ifdef LOCAL
    freopen("in.in","r",stdin);
    //freopen("out.out","w",stdout);
#endif
    int T=gi();
    while(T--){
        int n=gi(),m=gi(),x1=gi(),x2=gi();
        int xa=1-x1,ya=1+x1;
        int xb=n-x2,yb=n+x2;
        int d=(std::max(abs(xa-xb),abs(ya-yb))+1>>1)-1;
        if(x1==x2&&(n&1))++d;
        d=std::min(d,x1-1);
        d=std::min(d,m-x2);
        d=std::min(d,m-x1+n-1);
        d=std::min(d,x2-1+n-1);
        d=std::min(d,n-1);
        d=std::max(0,d);
        if(n==1)d=0;
        printf("%lld\n",1ll*d*d);
    }
    return 0;
}