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#include "mpi.h"
#include <stdio.h>
#include <string.h>

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

    int rank, size, i, buf[1];
    const int strsize = 100;
    char msg[strsize];
    MPI_Status status;

    //initialize MPI
    MPI_Init(&argc, &argv);

    //set the number of processes
    MPI_Comm_size(MPI_COMM_WORLD, &size);

    //set rank of all processes / nodes
    MPI_Comm_rank(MPI_COMM_WORLD, &rank);

    if(rank != 0 ){
        sprintf( msg, "msg from node %d out of %d nodes\n", rank, size);
        MPI_Send(msg, strlen(msg)+1, MPI_CHAR, 0, 0, MPI_COMM_WORLD );
    }
    else{
        for(i=1; i<size;i++ ){
            MPI_Recv(msg, strsize, MPI_CHAR, i, 0, MPI_COMM_WORLD, MPI_STATUS_IGNORE );
            printf("%s\n", msg);
        }
    }
    MPI_Finalize();
return 0;
}