{
    TFile *fin = new TFile("example_data.root");
    TH1D *hist = (TH1D *)fin->Get("hist");
    
    hist->SetFillColor(kRed-9);
    hist->SetStats(false);
    hist->GetXaxis()->SetTitle("Mass");
    
    TF1 *f1 = new TF1("f1","[0]+[1]*x+[2]*gaus(2)");
    f1->SetParameters(100.,-30.,20.,1.,0.05);
    hist->Fit("f1","L");
}