#include <bits/stdc++.h>
using namespace std;
#define int long long 
struct point{
    int x,y;
};
vector<point> points;
int x,y,r;
int n;
bool check(int xa,int ya,int xb,int yb)
{
    int A = ya - yb;
    int B = xb - xa;
    int C = -A * xa - B * ya;

    
    // Tính khoảng cách
    // return (double)(std::abs(A * x + B * y + C)) > r * (double)(std::sqrt(A * A + B * B));
    return (double)(std::abs(A * x + B * y + C)) - r * (double)(std::sqrt(A * A + B * B)) > -1e-9;

}

double areaOfTriangle(int x1, int y1, int x2, int y2, int x3, int y3) {
    return std::abs(x1 * (y2 - y3) + x2 * (y3 - y1) + x3 * (y1 - y2));
}

void solve()
{
    int l = 0, r = 1;
    int cur_area = 0;
    int max_area = 0;
    // cout<<points[1].x<<" "<<points[1].y<<" "<<points[4].x<<" "<<points[4].y<<"\n";
    // cout<<check(points[1].x, points[1].y, points[4].x, points[4].y)<<"\n";
    // return;
    for (int l = 0; l < n; l++) 
    {
        while (r < n && check(points[l].x, points[l].y, points[r].x, points[r].y)) 
        {
            cur_area += areaOfTriangle(points[l].x, points[l].y, points[r-1].x, points[r-1].y, points[r].x, points[r].y);
            r++;
        }
        max_area = max(max_area, cur_area);
        // cout<<l<<" "<<r<<" "<<cur_area<<"\n";
        cur_area -= areaOfTriangle(points[l].x, points[l].y, points[l+1].x, points[l+1].y, points[r-1].x, points[r-1].y);
    }
    reverse(points.begin(), points.end());
    l = 0, r = 1;
    cur_area = 0;
    for (int l = 0; l < n; l++) 
    {
        while (r < n && check(points[l].x, points[l].y, points[r].x, points[r].y)) 
        {
            cur_area += areaOfTriangle(points[l].x, points[l].y, points[r-1].x, points[r-1].y, points[r].x, points[r].y);
            max_area = max(max_area, cur_area);
            r++;
        }
        cur_area -= areaOfTriangle(points[l].x, points[l].y, points[l+1].x, points[l+1].y, points[r-1].x, points[r-1].y);
    }
    cout<<max_area<<"\n";
}

signed main()
{
    // if (fopen("thu.inp", "r"))
    //     freopen("thu.inp", "r", stdin);
    int tc; cin>>tc;
    while (tc--)
    {
        points.clear();
        cin>>n;
        cin>>x>>y>>r;
        for (int i = 1; i <= n; i++)
        {
            point a;
            cin>>a.x>>a.y;
            points.push_back(a);
        }
        solve();
    }
}