#include <mpi.h>
#include <iostream>
int main(int argc, char** argv) {
MPI_Init(&argc, &argv);
int rank = -1, size = -1;
MPI_Comm_rank(MPI_COMM_WORLD, &rank);
MPI_Comm_size(MPI_COMM_WORLD, &size);
std::cout << "Hello from rank " << rank << " out of " << size << "!" << std::endl;
MPI_Finalize();
return 0;
}