#include <vector>

typedef std::vector<TH1F*> HistVector_t;
typedef std::vector<TH1F*>::iterator HistVectorItr;


void TestMacro() {
TH1F* ht = new TH1F("ht", "TestHist", 100, -5, 5);	//template histogram

TH1F* h1 = ht->Clone("h2");
TH1F* h2 = ht->Clone("h2");
TH1F* h3 = ht->Clone("h3");

h1->FillRandom("gaus", 10000);

h2->FillRandom("pol2", 10000);
h2->SetLineColor(kRed);

h3->FillRandom("expo", 10000);
h3->SetLineColor(kBlue);

h1->Draw();
h2->Draw("same");
h3->Draw("same");

HistVector_t vec;
vec.push_back(&h2);
vec.push_back(&h3);

TH1F* hb = MergeHistograms(vec, ht, cout);
hb->SetLineColor(16);
hb->SetFillStyle(3005);

h1->Draw();
hb->Draw("same");

}

//////////////////////////////////////////////////////////////////////////////////////////////////


TH1F* MergeHistograms(HistVector_t &hvec, TH1F* hmodel, ostream& sout) {

  TH1F* h_bkg = (TH1F*)hmodel->Clone("h_bkg");
  sout << endl << "Merging "<< hvec.size() << " background histograms." << endl;  

  for(Int_t binc = 1; binc <= h_bkg->GetNbinsX(); binc++) {    //for each bin
  //for(HistVectorItr binc = hvec.begin(); binc != hvec.end(); ++binc)
    std::vector<Float_t> values;
	sout << "Bin " << binc << endl;
    //for(Int_t cc = 0; cc < hvec.size(); cc++) {       // for each background
	for( HistVectorItr itr = hvec.begin(); itr != hvec.end(); ++itr) {
	   sout << "histo " << endl;
	   Float_t vtemp = (*itr).GetBinContent(binc);   // fill values vector
	   sout << "value = " << vtemp << endl;
       values.push_back(vtemp);
    }
    //find max element
	sout << "Finding max el.." << endl;
    std::vector<Float_t>::iterator melement = max_element( values.begin(), values.end() );
    //sout << "Bin: " << binc << ", value= " << melement << endl;
    h_bkg->SetBinContent(binc, (*melement) );
  }
  
  return h_bkg;
}