Pi2 supercomputing
Execute the code MPI_08_b using 10, and then 12 nodes (see the following figure):

Execute the code using 14, and then 16 nodes (see the following figure):

Execute the code using 18, and then 20 nodes (see the following figure):

Execute the code using 22, and then 24 nodes (see the following figure):

Execute the code using 26, and then 28 nodes (see the following figure):

Execute the code using 30, and then 32 nodes (see the following figure):

The preceding runs were generated by the author's 8-node, 32 core, 32 GHz. Raspberry Pi2 supercomputer. If you are now feeling same as the all powerful Dr. Doom, and crave even more power at your fingertips, you can build an even faster machine by adding more Pi2s or the more advanced Pi3s.