#ifndef _common_h
#define _common_h

#include <math.h>
#include <fstream>
#include <vector>
#include <set>
#include <string>

using namespace std;

extern double lx, ly;
extern double x_0, y_0;

extern double Time;                   //elapsed real time
extern unsigned int no_of_particles;  //number of particles
extern ofstream fphase;
extern ofstream fenergy;

void step();
void make_forces();
void integrate();
void init_algorithm();
void phase_plot(ostream & os);
#endif