#include<cstdio>
#include<algorithm>
#include<cstring>
#define N 
using namespace std;
inline int read(){
    int x=0,f=1;
    char c=getchar();
    while(c<'0'||c>'9'){
        if(c=='-')f=-1;
        c=getchar();
    }
    while(c>='0'&&c<='9'){
        x*=10;x+=c-'0';
        c=getchar();
    }
    return x*f;
}
//int head[N],last;
//struct u2003{
//    int nx,b;
//}e[M];
//inline void build(int a,int b){
//    e[++last].b=b;
//    e[last].nx=head[a];
//    head[a]=last;
//}
int n,m,x1,x2;
inline void scan(){
    n=read();
    m=read();
    x1=read();
    x2=read();
}
inline int yin(){
    return x1-1<m-x2?x1-1:m-x2;
}
inline int ruan(){
    int x=abs(x1-x2);
    if(x==0)return (n+1)/2-1;
    return (n+x)/2-1;
}
long long ans;
inline void suan(){
    if(x1==1||x2==m)
        printf("0\n");
    else{
        ans=n-1;
        int ans1=yin();
        int ans2=ruan();
        ans=ans<ans2?ans:ans2;
        ans=ans<ans1?ans:ans1;
        ans*=ans;
        printf("%lld\n",ans);
    }
}
int t;
int main(){
    scanf("%d",&t);
    for(int i=1;i<=t;i++){
        scan();
        suan();
    }
}