/*
 ============================================================================
 Name        : labor6.c
 Author      : dan
 Version     :
 Copyright   : Your copyright notice
 Description : Hello MPI World in C
 ============================================================================
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include "mpi.h"

int main(int argc, char **argv) {
	int masca, dest, sursa,doi_la_k,k;
	int count, myrank;
	/* tag for messages */
	char mesaj[20]="Hello";/* storage for message */
	MPI_Init(&argc, &argv);
	MPI_Status status;
	MPI_Comm_rank(MPI_COMM_WORLD, &myrank);
	MPI_Comm_size(MPI_COMM_WORLD, &count);
	masca=(1<<3)-1;
	/* initializeaza cu 1 toti bitii mastii */
	for (k=2;k>=0;k--) {
		doi_la_k=(1<<k);
		masca=(masca^doi_la_k);
		/* seteaza pe 0 al k-lea bit al mastii */
		if ((myrank & masca)==0) {
			/* daca ultimii k biti sunt 0 */
			if ((myrank & doi_la_k)==0) {
				dest=myrank^doi_la_k;
				MPI_Send(mesaj, strlen(mesaj) + 1, MPI_CHAR, dest, 99,MPI_COMM_WORLD);
				printf("%d trimite catre %d \n", myrank,dest);
			} else {
				sursa = myrank^doi_la_k;
				MPI_Recv(mesaj, strlen(mesaj) + 1, MPI_CHAR, sursa, 99,MPI_COMM_WORLD, &status);
			}
		}
	}
	MPI_Finalize();
	return 0;
}