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

int main (int argc, char *argv[])
{
    int id, np, j;
    char processor_name[MPI_MAX_PROCESSOR_NAME], message[100];
    int processor_name_len;
    MPI_Status status;

    MPI_Init(&argc, &argv);

    MPI_Comm_size(MPI_COMM_WORLD, &np);
    MPI_Comm_rank(MPI_COMM_WORLD, &id);
    MPI_Get_processor_name(processor_name, &processor_name_len);

    /* want to do: print message to a string, then send this message
    from all proceesses to process 0, and have process 0 print them. */

    sprintf(message,
        "Hello world from process %03d out of %03d, processor name %s", 
        id, np, processor_name);

    if (id == 0) {
      printf("%s\n", message);
      for (j = 1; j < np; j++) {
        MPI_Recv(message,100,MPI_CHAR,j,0,MPI_COMM_WORLD, &status);  
        printf("%s\n", message);
      }
    } else {
      MPI_Send(message,1+strlen(message),MPI_CHAR,0,0,MPI_COMM_WORLD);
    }

    MPI_Finalize();
    return 0;
}