void graph(){
   c1 = new TCanvas("c1","Mwp_r.value",200,10,50,500);
   c1->SetGrid();
  TGraph *mg = new TMultiGraph();

  
   Int_t n = 11;
   Float_t xcls[n]  = {100,130,160,190,220,250,280,310,340,370,400};
   Float_t ycls[n]  = {0.045,0.125,0.245,0.305,0.485,0.795,0.825,1.395,1.995,2.715,3.835};

   Float_t xclsb0[n]  = {100,130,160,190,220,250,280,310,340,370,400};
   Float_t yclsb0[n] ={0.075,0.225,0.475,0.655,1.145,1.825,2.185,3.425,4.895,6.775,9.505};

   Float_t xcls_p[n]  = {100,130,160,190,220,250,280,310,340,370,400};
   Float_t yclsb_p[n]={0.055,0.155,0.335,0.455,0.805,1.285,1.545,2.415,3.445,4.785,6.745};

   Float_t xcls_m[n]  = {100,130,160,190,220,250,280,310,340,370,400};
   Float_t yclsb_m[n]={0.035,0.115,0.245,0.335,0.585,0.935,1.115,1.755,2.515,3.495,4.905};

   TGraph *gr1 = new TGraph(n,xcls,ycls);
   TGraph *gr2 = new TGraph(n,x,yclsb0,yclsb0);
   TGraph *gr3 = new TGraph(n,x,yclsb_p,yclsb_p);
   TGraph *gr4 = new TGraph(n,x,yclsb_m,yclsb_m)
  
   mg->Add(gr1);
   mg->Add(gr2);
   mg->Add(gr3);
   mg->Add(gr4);

   mg->SetTitle("TGraph m_rvalue");
   mg->GetXaxis()->SetTitle("wprime mass");
   mg->GetYaxis()->SetTitle("r_value");
   mg->GetXaxis()->CenterTitle();
   mg->GetYaxis()->CenterTitle();

  
   mg->Draw("AC");
}