laplace_mpi():
  C/MPI version
  Solve the Laplace equation using MPI.

  MPI has been set up.
  Initialize the matrix M.
  Set the list of neighbors.
  Begin the iteration.
  ITERATE gathered updated results to process 0.
  Task 1 took  0.011 seconds
  ITERATE gathered updated results to process 0.
  Task 2 took  0.011 seconds
  ITERATE gathered updated results to process 0.
  Task 3 took  0.011 seconds
  ITERATE gathered updated results to process 0.
did 560 iterations
  Task 0 took  0.011 seconds
  Solution written to "laplace_solution.txt".

LAPLACE_MPI:
  Normal end of execution.