#include <bits/stdc++.h>   using namespace std;   const double ep = 1e-6;   const double eps = 4e-5;   const double pi = acos(-1);   int tmpx, tmpy;   struct pnt {     double x, y;     pnt(double x = 0, double y = 0) : x(x), y(y) {}     pnt operator+(const pnt &b) const { return pnt(x + b.x, y + b.y); }     pnt operator-(const pnt &b) const { return pnt(x - b.x, y - b.y); }     pnt operator*(const double &b) const { return pnt(x * b, y * b); }     pnt operator/(const double &b) const { return pnt(x / b, y / b); }     double operator&(const pnt &b) const { return x * b.x + y * b.y; }     double operator^(const pnt &b) const { return x * b.y - y * b.x; }     double dist() { return sqrt(x * x + y * y); }     void input() { scanf( %d %d , &tmpx, &tmpy), x = tmpx, y = tmpy; }     void print() { printf( (%.4lf %.4lf) n , x, y); }   };   int n, Q;   pnt p[10101 << 1], q;   double s[10101 << 1], area;   void prep() {     for (int i = 0, j = n - 1; i < j; i++, j--) swap(p[i], p[j]);     for (int i = 0; i <= n; i++) p[i + n] = p[i];     s[0] = 0;     for (int i = 1; i <= 2 * n; i++) s[i] = s[i - 1] + (p[i - 1] ^ p[i]);     area = s[n];   }   double dist(pnt &p, double &a, double &b, double &c) {     return p.x * a + p.y * b + c;   }   pnt intersect(pnt &a, pnt &b, double &A, double &B, double &C) {     double a_ = dist(a, A, B, C);     double b_ = dist(b, A, B, C);     return (a * b_ - b * a_) / (b_ - a_);   }   double calc(double alpha) {     double A = sin(alpha), B = -cos(alpha), C = -A * q.x - B * q.y;     int st, en, u, v, mid;     double st_, en_, u_, v_, mid_;     st = 0, en = n - 1;     st_ = dist(p[st], A, B, C);     en_ = dist(p[en], A, B, C);     while (st < en) {       u = (st + en - 1) >> 1;       v = u + 1;       u_ = dist(p[u], A, B, C);       v_ = dist(p[v], A, B, C);       if ((st_ <= en_ && st_ <= v_) || (u_ <= en_ && u_ <= v_))         en = u;       else         st = v;     }     int mn = st;     st = 0, en = n - 1;     st_ = dist(p[st], A, B, C);     en_ = dist(p[en], A, B, C);     while (st < en) {       u = (st + en - 1) >> 1;       v = u + 1;       u_ = dist(p[u], A, B, C);       v_ = dist(p[v], A, B, C);       if ((st_ >= en_ && st_ >= v_) || (u_ >= en_ && u_ >= v_))         en = u;       else         st = v;     }     int mx = st;     st = mn, en = mx + n;     while (st < en - 1) {       mid = (st + en) >> 1;       mid_ = dist(p[mid], A, B, C);       if (mid_ < 0)         st = mid;       else         en = mid;     }     int ans1 = st % n;     pnt crs1 = intersect(p[ans1], p[ans1 + 1], A, B, C);     st = mx, en = mn + n;     while (st < en - 1) {       mid = (st + en) >> 1;       mid_ = dist(p[mid], A, B, C);       if (mid_ > 0)         st = mid;       else         en = mid;     }     int ans2 = st % n;     pnt crs2 = intersect(p[ans2], p[ans2 + 1], A, B, C);     if (ans1 >= ans2) ans2 += n;     double rlt = (p[ans2] ^ crs2) + (crs2 ^ crs1) + (crs1 ^ p[ans1 + 1]) +                  s[ans2] - s[ans1 + 1];     if (((crs1 - crs2) & pnt(cos(alpha), sin(alpha))) < 0) rlt = area - rlt;     return rlt;   }   int main() {     scanf( %d %d , &n, &Q);     for (int i = 0; i < n; i++) p[i].input();     prep();     while (Q--) {       q.input();       double st = 0, en = pi, mid, tmp;       bool stt = (calc(st) < area / 2), enn = !stt, midd;       for (int step = 1; step <= 42; step++) {         mid = (st + en) / 2;         tmp = calc(mid);         midd = (tmp < area / 2);         if (fabs(tmp * 2 - area) / area < eps) break;         if (midd == stt)           st = mid;         else           en = mid;       }       printf( %.20lf n , (st + en) / 2);     }     return 0;   }