#include <complex>
#include <vector>

#ifndef _PARTICLE_
#define _PARTICLE_

class Particle{
 public:
  ///Constructor & Dectructor
  Particle();
  Particle(double mass, double s, int p);
  virtual ~Particle(){};

  ///Get parameters of particle
  ///mass
  double M();
  ///momenta
  double S();
  ///helicity
  std::vector<double> lya();// obtain whole vector
  double lya(int k);//obtain k-th element from vector;
  ///P parity
  int P();

  void Print();

 private:
  double _s;//total moment
  std::vector<double> _lya;// moment projection
  double _mass; // mass of resonance
  int _p; 
};
#endif