{
auto C = new TCanvas();
auto h1 = new TH1D("h1","Background", 100,-1,1);
auto h2 = new TH1D("h2","Data", 100,-1,1);
h1->FillRandom("gaus",100000);
h2->FillRandom("gaus",100000);
h1->Draw("P");
h2->Fit("gaus","","SAME");
}
{
auto C = new TCanvas();
auto h1 = new TH1D("h1","Background", 100,-1,1);
auto h2 = new TH1D("h2","Data", 100,-1,1);
h1->FillRandom("gaus",100000);
h2->FillRandom("gaus",100000);
h1->Draw("P");
h2->Fit("gaus","","SAME");
}