#define _MPI_CPP_BINDINGS
#include <mpi.h>
#include <iostream>

using std::cout;
using std::endl;

int main(int argc, char* argv[])
{
  MPI::Init(argc, argv);
  
  const int size = MPI::COMM_WORLD.Get_size();
   if (size < 2) return MPI::ERR_SIZE;  //check for min 2 processes

  const int rank = MPI::COMM_WORLD.Get_rank();
  const int master = 0;

  if (rank == master)  //the master
  {
    double toSend = 13.13;
    const int cnt = 1;
    const int tag = 0;
    
    for (int dest=1; dest<size; ++dest)
    {
      cout << "process " << rank << " sends "<< toSend << " to process " << dest << endl;
      MPI::COMM_WORLD.Send(&toSend, cnt, MPI::DOUBLE, dest, tag);
    }
  }
  else
  {
    double toRecv;
    const int cnt = 1;
    const int from = master;
    const int tag = 0;  

    MPI::COMM_WORLD.Recv(&toRecv, cnt, MPI::DOUBLE, from, tag);  
    cout << "process " << rank << " received "<< toRecv << " from process " << from << endl;
  }
  MPI::Finalize();  
}