#include <iostream>
using namespace std;
#include <set>
#include <algorithm>
#include <cmath>
#include <map>
#include <cstdio>
#include <string>
#include <cstring>
#include <string.h>
#include <stdlib.h>
#include <iomanip>
#include <fstream>
#include <stdio.h>
#include <stack>
#include <queue>
#include <ctype.h>
#include <vector>
#include <random>
#include<list> 
#define double __int128
#define ll __int128
#define ull unsigned long long
#define pb push_back
#define rep(i, a, n) for (int i = a; i <= n; i++)
#define per(i, a, n) for (int i = n; i >= a; i--)
#define pii pair<int, int>
#define pli pair<ll, int>
#define pil pair<int, ll>
#define pll pair<ll, ll>
#define lowbit(x) ((x)&(-x))
ll extend_gcd(ll a, ll b, ll &x, ll &y)
{
    if (b == 0)
    {
        x = 1;
        y = 0;
        return a;
    }
    ll d = extend_gcd(b, a % b, y, x);
    y -= a / b * x;
    return d;
}
ll fastpow(ll a, ll n, ll mod)
{
    ll ans = 1;
    a %= mod;
    while (n)
    {
        if (n & 1)
            ans = (ans * a) % mod; //% mod
        a = (a * a) % mod;         //% mod
        n >>= 1;
    }
    return ans;
}

inline void write(__int128 x)
{
    if (x > 9)
    {
        write(x / 10);
    }
    putchar(x % 10 + '0');
}

struct Point
{
    double x,y;
    Point()
    {

    }
    Point(double x,double y):x(x),y(y)
    {

    }
    Point operator + (Point B)
    {
        return Point(x+B.x,y+B.y);
    }
    Point operator - (Point B)
    {
        return Point(x-B.x,y-B.y);
    }
    bool operator == (Point B)
    {
        return x-B.x==0&&y-B.y==0;
    }
    bool operator < (Point B)
    {
        return x-B.x<0||(x-B.x==0&&y-B.y<0);
    }
};
typedef Point Vector;
double Cross(Vector A,Vector B)//叉积
{
    return A.x*B.y-A.y*B.x;
}
int Convex_hull(Point *p,int n,Point *ch)
{
    n=unique(p,p+n)-p;
    sort(p,p+n);
    int v=0;

    for(int i=0;i<n;i++)
    {
        while (v>1&&Cross(ch[v-1]-ch[v-2],p[i]-ch[v-1])<=0)
        {
            v--;
        }
        ch[v++]=p[i];
    }

    int j=v;

    for(int i=n-2;i>=0;i--)
    {
        while (v>j&&Cross(ch[v-1]-ch[v-2],p[i]-ch[v-1])<=0)
        {
            v--;
        }
        ch[v++]=p[i];
    }
    if(n>1)
    {
        v--;
    }
    return v;
}


int dir[4][2] =
    {
        {-1, 0}, {0, 1}, {1, 0}, {0, -1}}; // 左右上下
// int dir[8][2]={
//         {-1, 0}, {0, 1}, {1, 0}, {0, -1},{-1,-1},{-1,1},{1,-1},{1,1}
// };

const ll mod1 = 998244353ll, P1 = 131, mod2 = 1e9 + 7ll, P2 = 13331;
ll inverse(ll x)
{
    return fastpow(x,mod1-2,mod1);
}

const int N = 1e6 + 10, M = 1e6 + 10;

///////////////////////////////////

int tt;
int n;
Point p[N],ch[N],c;
ll R;

///////////////////////////////////

inline ll read()
{
    ll x=0,f=1;
    char ch=getchar();
    while(ch<'0'||ch>'9')
    {
        if(ch=='-')
            f=-1;
        ch=getchar();
    }
    while(ch>='0' && ch<='9')
        x=x*10+ch-'0',ch=getchar();
    return x*f;
}


///////////////////////////////////

void init()
{

}

///////////////////////////////////

int main()
{
   // freopen("ain.txt", "r", stdin); freopen("aout.txt", "w", stdout);
    cin>>tt;
    while (tt--)
    {
        n=read();
        c.x=read();
        c.y=read();
        R=read();
        rep(i,0,n-1)
        {
            p[i].x=read();
            p[i].y=read();
        }
        int v=Convex_hull(p,n,ch);
        ll ans=0;
        int r=1,rr=2;
        ll S=0;
        rep(leftt,0,v-1)
        {
            while (1)
            {
                rr=(r+1)%v;
                ll temp=Cross(c-ch[rr],ch[leftt]-ch[rr]);
                if(temp<0)
                {
                    break;
                }
                ll dis=(ch[leftt].x-ch[rr].x)*(ch[leftt].x-ch[rr].x)+(ch[leftt].y-ch[rr].y)*(ch[leftt].y-ch[rr].y);
                if(Cross(ch[leftt]-ch[rr],c-ch[rr])*Cross(ch[leftt]-ch[rr],c-ch[rr])<dis*R*R)
                {
                    break;
                }
                S+=Cross(ch[leftt]-ch[rr],ch[r]-ch[rr]);   
                ans=max(ans,S);
                r=rr;
            }
            int nxtleftt=(leftt+1)%v;
            S-=Cross(ch[leftt]-ch[r],ch[nxtleftt]-ch[r]);   
        }
        write(ans);
        putchar('\n');
    }

    return 0;
}