#include <bits/stdc++.h>
typedef long long ll;
using namespace std;
const int maxn = 1e5 + 5;
int n;
ll R;
struct vec {
	ll x, y;
	vec(int x = 0, int y = 0) : x(x), y(y) {}
	friend vec operator - (const vec &p, const vec &q) {
		return vec(p.x - q.x, p.y - q.y);
	}
} a[maxn * 2], c;
ll cross(vec p, vec q) {
	return p.x * q.y - p.y * q.x;
}
bool check(vec p, vec q) {
	// cout <<sqrt((p.x - q.x) * (p.x - q.x) + (p.y - q.y) * (p.y - q.y)) << '\n';
	// cout << (p.y - q.y) * c.x << ' ' << (q.x - p.x) * c.y << ' ';
	// cout << abs((p.y - q.y) * c.x + (q.x - p.x) * c.y + p.x * q.y - p.y * q.x) << ' ';
	// cout << abs((p.y - q.y) * c.x + (q.x - p.x) * c.y + p.x * q.y - p.y * q.x)
	// / sqrt((p.x - q.x) * (p.x - q.x) + (p.y - q.y) * (p.y - q.y)) << '\n';
	return 1.0 * abs((p.y - q.y) * c.x + (q.x - p.x) * c.y + p.x * q.y - p.y * q.x)
	/ sqrt((p.x - q.x) * (p.x - q.x) + (p.y - q.y) * (p.y - q.y)) >= R;
}
void solve() {
	cin >> n >> c.x >> c.y >> R;
	for(int i = 1; i <= n; i++) {
		cin >> a[i].x >> a[i].y;
		a[i + n] = a[i];
	}
	ll ans = 0, sum1 = 0, sum2 = 0;
	sum1 += cross(a[1], a[1]);
	for(int i = 1; i <= n; i++) {
		sum2 += cross(a[i], a[i + 1]);
	}
	for(int i = 1, j = 1; i <= n; i++) {
		while(j + 1 - i <= n - 2 && check(a[i], a[j + 1]) && cross(a[j + 1] - a[i], c - a[i]) > 0) {
			sum1 += cross(a[j], a[j + 1]);
			sum1 -= cross(a[j], a[i]);
			sum1 += cross(a[j + 1], a[i]);
			// sum2 -= cross(a[j], a[j + 1]);
			// sum2 -= cross(a[j], a[i + n]);
			// sum2 += cross(a[j + 1], a[i + n]);
			j++;
		}
		if(i < j) {
			ans = max(ans, abs(sum1));
			// cout << i << ' ' << j << ' ' << sum1 << '\n';
			// if(cross((a[j] - a[i]), (c - a[i])) < 0) {
			// ans = max(ans, sum1 / 2);
			// }
			// else {
			// ans = max(ans, sum2 / 2);
			// }
			sum1 -= cross(a[i], a[i + 1]);
			sum1 -= cross(a[j], a[i]);
			sum1 += cross(a[j], a[i + 1]);
			// sum2 += cross(a[i + n], a[i + n + 1]);
			// sum2 -= cross(a[j], a[i + n]);
			// sum2 += cross(a[i + n + 1], a[j]);
		}
		else {
			j++;
		}
	}
	cout << ans << '\n';
}
int main() {
#ifdef yczDEBUG
	freopen("1.in", "r", stdin);
	freopen("1.out", "w", stdout);
#endif
	ios::sync_with_stdio(0);
	cin.tie(0);
	int T;
	cin >> T;
	while(T--) {
		solve();
	}
	return 0;
}