Plotting run time of algorithm

suppose i have two algorithm. after running i have got run time of that two algorithm 5sec,7sec respectively. I have run for different number of samples:

                    samples1          run time            samples2      runtime

                         512              5sec              512          7sec

                         350              3sec              350          4.45 sec

                         100              0.333 sec         100          1 sec

Now how to plot above data at a time for samples1 and anmother at a time for samples2. I have used tic-toc but not getting the result. It shows blank graph. Please help