hypeMerge(char *filename="")
{
/*
 Author: G. Bonomi
 Date:   9 June 2005
 This macro open a data file containing a list of runs (one run x line)
 and merge the h126 ntuples in a new ROOT file called: 
 hype_fromXXX_toYYY.root in the $HIS directory (where XXX and YYY are the
                                          first and last run)
 Input:  filename (file containing a list of runs (one run x line))
 Output: $HIS/hype_fromXXX_toYYY.root
*/
 FILE *rdat;
 int nrun=0,runs[2000],check,sl;
 char name[100],comando[100];
  
 if (!strcmp(filename,"")) {
    printf("Please pass a filename as an argument:\n [0].x merge.C(\"exam.dat\")\n");
    return;
 } 

/* It opens the file with the list of runs to be analyzed */
 rdat=fopen(filename,"r");
 if(rdat==NULL) {
  printf("File doesn't exist\n");
  return;
 }

  while(check=fscanf(rdat,"%d",&runs[nrun])>-1){
    nrun++;
  }

 fclose(rdat);
/* --->   <--- */




  TChain *bChain=new TChain("bChain");
  char bntp[100];
   //Default max size          1900000000
  TTree::SetMaxTreeSize(2146000000);
  //TTree::SetMaxTreeSize(3000000000);
  


  for(int i=0; i<nrun; i++) {
  if(runs[i]<10)       sprintf(bntp,"../histos/run0000%d_his.root/h126",runs[i]);
  else if(runs[i]<100) sprintf(bntp,"../histos/run000%d_his.root/h126",runs[i]);
  else if(runs[i]<1000) sprintf(bntp,"../histos/run00%d_his.root/h126",runs[i]);
  else if(runs[i]<10000) sprintf(bntp,"../histos/run0%d_his.root/h126",runs[i]);
  bChain->Add(bntp);
 }

/*
  for(int i=0; i<nrun; i++) {
  if(runs[i]<10)       sprintf(bntp,"/fidata3/datiFinuda/HISTPROD04/FINU0000%d.root/h126",runs[i]);
  else if(runs[i]<100) sprintf(bntp,"/fidata3/datiFinuda/HISTPROD04/FINU000%d.root/h126",runs[i]);
  else if(runs[i]<1000) sprintf(bntp,"/fidata3/datiFinuda/HISTPROD04/FINU00%d.root/h126",runs[i]);
  else if(runs[i]<10000) sprintf(bntp,"/fidata3/datiFinuda/HISTPROD04/FINU0%d.root/h126",runs[i]);
  bChain->Add(bntp);
 }
*/
  sprintf(bntp,"../histos/hype_from%d_to%d.root",runs[0],runs[nrun-1]);

   printf("Creating %s file\n",bntp);
   bChain->Merge(bntp); 
 
}