#include <stdio.h>
#include <iostream>
#include <string>
#include <fstream>
#include <sstream>
#include <TString.h>
#include <TFile.h>
#include <TTree.h>

void make_ttree(TString filename){
  //constant
  int nsample = 1023;
  
  //global variable
  double voltage[nsample];
  double value;
  std::cout << "FILENAME : " << filename << std::endl;
  std::ifstream data(filename);

  TString rootfile_name = filename.ReplaceAll(".txt",".root");
  TFile *rootfile = new TFile(rootfile_name,"recreate");
  TTree * tree = new TTree("tree","tree");

  tree->Branch("nsample",&nsample,"nsample/I");
  tree->Branch("voltage",voltage,"voltage[nsample]/D");

  std::string line;
  int j = 0;
  int i = 0;
  while(std::getline(data,line))
  {
    voltage[i] = stod(line);
    std::cout << "time  " << i << " : " << voltage[i] << std::endl;
    i++;
    if(i == nsample)
    {
      tree->Fill();
      i = 0;
      j++;
    }
  }
  std::cout << "# of event : " << j << std::endl;
  tree->Write();
  rootfile->Close();
  return 0;
}