#include<bits/stdc++.h>
#define LL long long
#define LD long double
#define fr(x) freopen(#x".in","r",stdin);freopen(#x".out","w",stdout);
using namespace std;
const int N=1e5+5;
int T,n;LD r;
struct comp{LD x,y;}a[N],O;
inline LD p2(LD x){return x*x;}
inline comp operator+(comp A,comp B){return {A.x+B.x,A.y+B.y};}
inline comp operator-(comp A,comp B){return {A.x-B.x,A.y-B.y};}
inline LD operator*(comp A,comp B){return A.x*B.y-A.y*B.x;}
inline LD dis(comp A,comp B){return p2(A.x-B.x)+p2(A.y-B.y);}
inline bool chk(comp A,comp B)
{
	if(A.x==B.x) return fabsl(A.x-O.x)>=r;
	if(A.y==B.y) return fabsl(A.y-O.y)>=r;
	LD k=(A.y-B.y)/(A.x-B.x),b=A.y-k*A.x,_k=-1/k,_b=O.y-_k*O.x;
	LD X=(_b-b)/(k-_k),Y=k*X+b;
	return dis({X,Y},O)>=r*r;
}
int main()
{
	ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);cin>>T;
	while(T--)
	{
		cin>>n>>O.x>>O.y>>r;LL ans=0,s=0;
		for(int i=1;i<=n;i++) cin>>a[i].x>>a[i].y,a[i+n]=a[i];
		for(int i=1,j=1;i<=n;i++)
		{
			while(j+1<i+n&&chk(a[i],a[j+1])&&(O-a[i])*(a[j+1]-a[i])<=0) s+=fabsl((a[j]-a[i])*(a[j+1]-a[j])),j++;
			ans=max(ans,s);s-=fabsl((a[j]-a[i+1])*(a[i+1]-a[i]));
			
		}cout<<ans<<"\n";
	}
	return 0;
}