void DoChain(int m,int k,int j){
  TChain chain("pi0pippimeta__B4_M17_Tree");
  for (int i=0;i<10;i++){
    char myfile[200];
    sprintf(myfile,"/cache/halld/RunPeriod-2018-01/analysis/ver03/tree_pi0pippimeta__B4_M17/merged/tree_pi0pippimeta__B4_M17_04%d%d%d%d.root",m,k,j,i);
    chain.Add(myfile);
  }
  gROOT->ProcessLine(".x $ROOT_ANALYSIS_HOME/scripts/Load_DSelector.C");
  chain.Process("DSelector_omegaeta.C+");
}