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#include "animation.hpp"

int main(int argc, char* argv[]) {
  unsigned N = 1200;
  double R = 0.021;
  double ε = 0.01;
  unsigned steps = 1e6;

  initializeAnimation(argc, argv);

  Rng r;

  Model<2, HardSphere<2>> m(N, 2 * R);

  for (unsigned i = 0; i < N; i++) {
    Position<2> x = {r.uniform(0.0, 1.0), r.uniform(0.0, 1.0)};
    double rad = pow(r.uniform(pow(2.219, -2), 1.0), -0.5) * R / 2.219;
    m.insert(HardSphere<2>(x, rad));
  }

  for (unsigned i = 0; i < steps * N; i++) {
    HardSphere<2>& s = r.pick(m.particles);
    Vector<2> Δx;
    for (double& Δxi : Δx) {
      Δxi = r.variate<double, std::normal_distribution>(0, ε);
    }

    m.metropolis(1, s, Δx, r);

    HardSphere<2>& s1 = r.pick(m.particles);
    HardSphere<2>& s2 = r.pick(m.particles);

    Vector<2> t1 = s1.x;
    Vector<2> t2 = s2.x;
    Vector<2> t = (t1 + t2) / 2;

    Matrix<2> mat;

    mat(0, 0) = -1;
    mat(1, 1) = -1;
    mat(0, 1) = 0;
    mat(1, 0) = 0;

    Euclidean<2> g(t - mat * t, mat);

    std::cout << m.clusterFlip(1, g, s1, r) << std::endl;

    if (i % (N) == 0) {
      draw(m);
    }
  }

  return 0;
}