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

#define MASTER 0

int main(int argc, char **argv)
{
   int id, nproc;
   char stavek[100];

   MPI_Init(&argc, &argv);
   MPI_Comm_size(MPI_COMM_WORLD, &nproc);
   MPI_Comm_rank(MPI_COMM_WORLD, &id);

   if (id == MASTER)
   {
      printf("Vnesite stavek za igro telefon: ");
      fgets(stavek, 100, stdin);
      MPI_Send(stavek, 100, MPI_CHAR, id + 1, 0, MPI_COMM_WORLD);
      MPI_Recv(stavek, 100, MPI_CHAR, nproc - 1, 0, MPI_COMM_WORLD, MPI_STATUS_IGNORE);
      printf("%d -> %d: %s\n",nproc-1,id, stavek);
   }
   else
   {
      MPI_Recv(stavek, 100, MPI_CHAR, id - 1, 0, MPI_COMM_WORLD, MPI_STATUS_IGNORE);
      sleep(id-1);
      printf("%d -> %d: %s\n",id-1,id, stavek);
      for (int i = 0; i < 100; i++)
      {
         if (id == 1)
         {
            if (stavek[i] == 'e')
            {
               stavek[i] = 'a';
            }
            else if (stavek[i] == 'E')
            {
               stavek[i] = 'A';
            }
         }
         else if (id == 2)
         {
            if (stavek[i] == 't')
            {
               stavek[i] = 'm';
            }
            else if (stavek[i] == 'T')
            {
               stavek[i] = 'M';
            }
         }
         else if (id == 3)
         {
            if (stavek[i] == 'h')
            {
               stavek[i] = 'p';
            }
            else if (stavek[i] == 'H')
            {
               stavek[i] = 'P';
            }
         }
      }
      MPI_Send(stavek, 100, MPI_CHAR, (id + 1) % nproc, 0, MPI_COMM_WORLD);
   }

   MPI_Finalize();
   return 0;
}