Program 5

#include <mpi.h>

#include <stdio.h>

int main(int argc, char** argv) {

    int rank, size;

    int number;

    MPI_Init(&argc, &argv);              

    MPI_Comm_rank(MPI_COMM_WORLD, &rank);

    MPI_Comm_size(MPI_COMM_WORLD, &size);

    if (size < 2) {

        if (rank == 0) {

            printf("This program requires at least 2 processes.\n");

        }

        MPI_Finalize();

        return 0;

    }

    if (rank == 0) {

        number = 100;  

        printf("Process 0 sending number %d to Process 1\n", number);

        MPI_Send(&number, 1, MPI_INT, 1, 0, MPI_COMM_WORLD);

    } else if (rank == 1) {

        MPI_Recv(&number, 1, MPI_INT, 0, 0, MPI_COMM_WORLD, MPI_STATUS_IGNORE);

        printf("Process 1 received number %d from Process 0\n", number);

    }

    MPI_Finalize();

    return 0;

}

run commands

(if mpicc not installed-->sudo apt install openmpi-bin libopenmpi-dev)

mpicc prg.c -o prg

mpirun -np 2 ./prg