I am not sure how to phrase this question correctly, but this is what I am trying to do. A single histogram can be plotted using cern ROOT with a following command, (TH1F*)electron->Draw(); But I have tens of histograms named in a sequence, such as electron1, elecron2, electron3, etc, and I want to write a simple loop to plot them all. I tried using sprintf and a simple for loop, but ROOT doesn't like it. char name[20]; (TH1F*)electron->Draw(); for(int j=0;j<5;j++){ sprintf(name, "%s%d","electron",j); (TH1F*)name->Draw("same"); } What am I doing wrong? Thanks in advance.