// random generator trouble (TRandom2 or TRandom3 have no such trouble)

/*
 * Compile with g++ -v -o example `rootconfig --cflags --libs` example.C 
 */

using namespace std;

#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <iomanip>
#include <iostream>

#include <TROOT.h>
#include <TTree.h>
#include <TMath.h>
#include <TFile.h>
#include <TRandom.h>

// Constants

const int NEvt = 100000;
float seed = 0; //seed for random generators
float GetBe11State(float E, float Width);

TRandom *rootrand = new TRandom();

// Main Program

int main(unsigned int argc, char **argv)
{
	int Evt;
	float EBe11;
	
	// Reading argc and argv
	
	if (argc!=2)
	{
		printf("(only) one argument needed... \n");
		//exit(0);
	}
	
	seed = atof(argv[1]);
	
	seed = fmod(seed,RAND_MAX);
	printf("Random seed = %f \n",seed);
	
	rootrand->SetSeed((int)seed);
	//gRandom->SetSeed((int)seed); //this produces the same bad results, of course
	srand((int)seed); 
	
	
	TFile *f = new TFile("filesave.root","RECREATE");
	
	TTree *mc = new TTree("mc","MonteCarlo Simulation");
		
	mc->Branch("EBe11",&EBe11,"EBe11/F");
	
	/************************************ Start of the Monte-Carlo **************************/
	
	for (Evt=1 ; Evt<=NEvt ; Evt++)
    {
		
		if (Evt%(NEvt/20)==0) printf("Treated Events: %d %% \n",(100*Evt/NEvt));
		
		EBe11 = GetBe11State(8.816,0.2);
				
		mc->Fill();
		
    }
	
	f->Write();
	
	return 1;
}

		
float GetBe11State(float E, float Width)
{	
	float EState = (float)rootrand->BreitWigner(E,Width); //rootrand is our TRandom object
	
	#ifdef EDEBUG
		cout << "GetBe11State w/index=" << index << "EBe11= " << E << " EState= " << EState << endl;
	#endif
	
	return ( EState );
}