How to compare results from three different programs together

I have three programs (attached below). each calculates delay. now i want to plot a graph between delay versus number of nodes(rows) from the three programs together and thus compare them. plz help....

Answer 1

[Thorsten]

 nodes = 100; % or how many nodes you want
 d1 = dtdma2(nodes);
 d2 = stdma2(nodes);
 d3 = csma2(nodes);
 plot(1:nodes, d1, 1:nodes, d2, 1:nodes, d3)