Solve Random walk problem with Monte Carlo Method

gridWalk.C

{
    TH2F *h = new TH2F("h","h",10,0,9,10,0,9);
    TCanvas *c = new TCanvas("c","c");
    c->Range(-0.3373713,-2.125,3.036341,9.125);
    //new TCanvas;
    //gPad->Range(-0.3373713,-2.125,3.036341,9.125);
    gStyle->SetOptStat(0);

    c->cd();
    h->SetTitle("");
    h->Draw();
    TLine *hline;
    Int_t ci;
    for (int i=0; i<10; i++){
        hline = new TLine(i,0,i,9);
        ci = TColor::GetColor("#0B3861");
        hline->SetLineColor(ci);
        hline->SetLineWidth(3);
        hline->Draw("same");
        hline = new TLine(0,i,9,i);
        ci = TColor::GetColor("#B45F04");
        hline->SetLineColor(ci);
        hline->Draw("same");
    }

    
    TPad *l = new TPad("l","l",0.24,0.75,0.3,.84);
    l->SetFillStyle(4000);
    l->Draw();
    l->cd();
    TImage *img = TImage::Open("users.gif");
    img->Draw();
    l->Update();
    //delete l;
    //delete img;
    c->cd();
    TPad *l2 = new TPad("l2","l2",0.74,0.27,0.82,0.35);
    l2->SetFillStyle(4000);
    l2->Draw();
    l2->cd();
    TImage *img2 = TImage::Open("users.gif");
    img2->Draw();
    l2->Update();
    c->Print("plots/walkMap.png");
    
}