#include "TTree.h"
#include "TFile.h"

class Tree_Maker
{
public:
  int A;
  double B[2];

  Tree_Maker(TTree *tree);
};

Tree_Maker::Tree_Maker(TTree *tree)
{
  tree->Branch("A", &A, "A/I");
  tree->Branch("B", B, "B[2]/D");
}

void Norm_mthd_4_tree()
{
  TFile *fout = new TFile("norm_mthd.root", "RECREATE");
  TTree *tree = new TTree("tree", "tree");
  Tree_Maker *data_tree = new Tree_Maker(tree);

  for (int i=0; i<10; i++)
  {
    data_tree->A = 0;
    data_tree->B[0] = -1;
    data_tree->B[1] = +1;

    tree->Fill();
  }

  fout->Write();
  fout->Close();
}