import static java.lang.Math.*;
import static java.util.Arrays.*;
import java.util.*;

public class Main {
	Scanner sc = new Scanner(System.in);
	
	void run() {
		int M = sc.nextInt(), N = sc.nextInt();
		P[] ps = new P[M], qs = new P[N];
		for (int i = 0; i < M; i++) ps[i] = new P(sc.nextInt(), sc.nextInt());
		for (int i = 0; i < N; i++) qs[i] = new P(sc.nextInt(), sc.nextInt());
		double res = 0, area = 0;
		for (int i = 0; i < N; i++) {
			P[] vs = ps;
			for (int j = 0; j < N; j++) if (i != j) {
				P p1 = qs[i].add(qs[j]).mul(0.5), p2 = p1.add(qs[j].sub(qs[i]).rot90());
				vs = convexCut(vs, p1, p2);
			}
			int n = vs.length;
			for (int j = 0; j < n; j++) {
				P p1 = vs[j].sub(qs[i]), p2 = vs[(j + 1) % n].sub(qs[i]);
				res += f(p1, p2);
				area += p1.det(p2);
			}
		}
		System.out.printf("%.10f%n", res / area / 6);
	}
	
	double f(P s, P t) {
		return g(s.x, t.x) * (t.y - s.y) - g(s.y, t.y) * (t.x - s.x);
	}
	
	double g(double s, double t) {
		return (s * s + t * t) * (s + t);
	}
	
	double EPS = 1e-10;
	int sig(double d) {
		return (d < -EPS) ? -1 : (d > EPS) ? 1 : 0;
	}
	
	class P {
		double x, y;
		P(double x, double y) {
			this.x = x;
			this.y = y;
		}
		P add(P p) {
			return new P(x + p.x, y + p.y);
		}
		P sub(P p) {
			return new P(x - p.x, y - p.y);
		}
		P mul(double d) {
			return new P(x * d, y * d);
		}
		double det(P p) {
			return x * p.y - y * p.x;
		}
		double abs2() {
			return x * x + y * y;
		}
		P rot90() {
			return new P(-y, x);
		}
	}
	
	P[] convexCut(P[] ps, P p1, P p2) {
		int n = ps.length;
		ArrayList<P> res = new ArrayList<P>();
		for (int i = 0; i < n; i++) {
			int d1 = sig(p2.sub(p1).det(ps[i].sub(p1)));
			int d2 = sig(p2.sub(p1).det(ps[(i + 1) % n].sub(p1)));
			if (d1 >= 0) res.add(ps[i]);
			if (d1 * d2 < 0) res.add(isLL(p1, p2, ps[i], ps[(i + 1) % n]));
		}
		return res.toArray(new P[0]);
	}
	
	P isLL(P p1, P p2, P q1, P q2) {
		double d = q2.sub(q1).det(p2.sub(p1));
		if (abs(d) < EPS) return null;
		return p1.add(p2.sub(p1).mul(q2.sub(q1).det(q1.sub(p1)) / d));
	}
	
	public static void main(String[] args) {
		new Main().run();
	}
}