Hello MPI

hello_mpi.c

#include <stdio.h>
#include <stdlib.h>
#include <mpi.h>

#define WORKER(id) if (ID == (id))
#define MASTER WORKER(0)

int main(int argc, char *argv[])
{
	int numprocs, ID;

	MPI_Init(&argc, &argv);
	MPI_Comm_size(MPI_COMM_WORLD, &numprocs);
	MPI_Comm_rank(MPI_COMM_WORLD, &ID);

	MASTER printf("Master %d: Hello MPI!\n", ID);
	else printf("Worker %d: Hello MPI!\n", ID);

	MPI_Finalize();

	return 0;
}