#include <cstdio>
#include <algorithm>
using namespace std;
typedef long long ll;
const int N=100003;
int read(){
	char c=getchar();int x=0;bool f=0;
	while(c<48||c>57) f|=(c=='-'),c=getchar();
	do x=x*10+(c^48),c=getchar();
	while(c>=48&&c<=57);
	if(f) return -x;
	return x;
}
struct Vec{
	int x,y;
	Vec(int X=0,int Y=0):x(X),y(Y){}
	friend Vec operator-(const Vec a,const Vec b){
		return Vec(a.x-b.x,a.y-b.y);
	}
	friend ll operator*(const Vec a,const Vec b){
		return (ll)a.x*b.y-(ll)a.y*b.x;
	}
	ll norm(){return (ll)x*x+(ll)y*y;}
}ct,a[N];
void solve(){
	int n=read();
	ct.x=read();ct.y=read();int r=read();
	for(int i=1;i<=n;++i) a[i].x=read(),a[i].y=read(),a[i+n]=a[i];
	ll area=0,res=0;
	for(int i=1,j=i+1;i<=n;++i){
		while(true){
			ll S=(a[j]-a[i])*(ct-a[i]);
			if(S<0||(__int128)S*S<(__int128)r*r*(a[j]-a[i]).norm()) break;
			res=max(res,area);
			area+=(a[j+1]-a[j])*(a[i]-a[j]);++j;
		}
		area-=(a[i+1]-a[i])*(a[j]-a[i]);
	}
	printf("%lld\n",res);
}
int main(){
	int tc=read();
	while(tc--) solve();
	return 0;
}