{
#include <fstream.h>
c1=new TCanvas("c1","c1",200,100,700,500);
double x1[200], xf1[200], x2[200], xf2[200], q2;

//
double ndata[2],x[2][1000],Q2[2][1000];
double up[2][1000], down[2][1000],upbar[2][1000],downbar[2][1000],
       strange[2][1000], charm[2][1000], bottom[2][1000], gluon[2][1000];

for(int i=0; i<2; i++) {
  int n = 0;
  ifstream fin("MSTW_100.txt");
  if(i==0) ifstream fin("MSTW_10000.txt");
  char line[255];
  fin.getline(line,sizeof(line)); // skip the 1st dummy line
  while (fin >> x[i][n]>>Q2[i][n]>>up[i][n]>>down[i][n]>>upbar[i][n]
  >>downbar[i][n]>>strange[i][n]>>charm[i][n]>>bottom[i][n]>>gluon[i][n]){
     n++;
  }
  ndata[i] = n;
  fin.close();
}
//
gPad->SetLogx();
gPad->SetLogy();
leg = new TLegend(0.73 ,0.6 ,0.92,0.93,"MSTW/MRSTMcal");
for(int i=0; i<2; i++) {
   ggluon = new TGraph(ndata[i],x[i],gluon[i]);
   gup = new TGraph(ndata[i],x[i],up[i]);
   gdown = new TGraph(ndata[i],x[i],down[i]);
   gstrange = new TGraph(ndata[i],x[i],strange[i]);
   gcharm = new TGraph(ndata[i],x[i],charm[i]);
   gbottom = new TGraph(ndata[i],x[i],bottom[i]);   
   ggluon -> GetXaxis()->SetTitle("x");
   ggluon -> GetYaxis()->SetTitle("xf(x)");
   ggluon -> SetLineColor(1); gup -> SetLineColor(2); gdown -> SetLineColor(3);
   gstrange -> SetLineColor(4); gcharm -> SetLineColor(5); gbottom -> SetLineColor(6);
   ggluon -> SetLineStyle(2-i); gup-> SetLineStyle(2-i);   gdown->SetLineStyle(2-i); 
   gstrange ->SetLineStyle(2-i);gcharm-> SetLineStyle(2-i);gbottom-> SetLineStyle(2-i); 
   ggluon -> SetMaximum(40.);
   ggluon -> SetMinimum(0.01);
   if(i==0) ggluon->Draw("AL");
   else ggluon -> Draw("SAME L");
   gup -> Draw("SAME L");    gdown -> Draw("SAME L");    gstrange -> Draw("SAME L"); 
   gcharm -> Draw("SAME L"); gbottom -> Draw("SAME L");  
   if(i==0){
      leg->AddEntry(ggluon,  "gluon   100 GeV^{2}","l");
      leg->AddEntry(gup,     "up      100 GeV^{2}","l");
      leg->AddEntry(gdown,   "down    100 GeV^{2}","l");
      leg->AddEntry(gstrange,"strange 100 GeV^{2}","l");
      leg->AddEntry(gcharm,  "charm   100 GeV^{2}","l");
      leg->AddEntry(gbottom, "bottom  100 GeV^{2}","l");
   } else {
      leg->AddEntry(ggluon,  "gluon   10000 GeV^{2}","l");
      leg->AddEntry(gup,     "up      10000 GeV^{2}","l");
      leg->AddEntry(gdown,   "down    10000 GeV^{2}","l");
      leg->AddEntry(gstrange,"strange 10000 GeV^{2}","l");
      leg->AddEntry(gcharm,  "charm   10000 GeV^{2}","l");
      leg->AddEntry(gbottom, "bottom  10000 GeV^{2}","l");
   }
}
leg->SetFillColor(10);
leg->SetBorderSize(0);
leg->Draw(); 
//
c1->Print("pdf_100vs10000.png");
}