/*
 * Circuit.c
 *
 *  Created on: Aug 20, 2010
 *      Author: Djordje
 */

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

#define EXTRACT_BIT(n, i) ((n&(1<<i))?1:0)

int main(int argc, char *argv[])
{
	int global_solution; //Total number of solutions
	int i;
	int id; //Process rank
	int p; //Num of processes
	int solutions; /*Solutions found by this process*/
	int check_circuit (int, int);
	double elapsed_time;

	MPI_Init(&argc, &argv);
	MPI_Barrier(MPI_COMM_WORLD);
	elapsed_time = - MPI_Wtime();
	MPI_Comm_rank(MPI_COMM_WORLD, &id);
	MPI_Comm_size(MPI_COMM_WORLD, &p);

	solutions = 0;
	for(i = id; i < 65536; i += p)
		solutions += check_circuit(id, i);

	MPI_Reduce(&solutions, &global_solution, 1 , MPI_INT, MPI_SUM, 0, MPI_COMM_WORLD);
	elapsed_time += MPI_Wtime();
	printf("Process %d is done\n", id);
	fflush(stdout);
	MPI_Finalize();
	if (id == 0) printf("There are %d different solutions. Elapsed time is %f\n", global_solution, elapsed_time);
	return 0;
}

int check_circuit(int id, int z)
{
	int v[16];
	int i;

	for(i = 0; i <16; i++) v[i] = EXTRACT_BIT(z, i);

	if((v[0] || v[1]) && (!v[1] || !v[3]) && (v[2] || v[3])
			&& (!v[3] || !v[4])  && (v[4] || !v[5])
			&& (v[5] || !v[6])   && (v[5] || v[6])
			&& (v[6] || !v[15])  && (v[7] || !v[8])
			&& (!v[7] || !v[13]) && (v[8] || v[9])
			&& (v[8] || !v[9])   && (!v[9] || !v[10])
			&& (v[9] || v[11])   && (v[10] || v[11])
			&& (v[12] || v[13])  && (v[13] || !v[14])
			&& (v[14] || v[15]))
	{
		/*printf("%d) %d%d%d%d%d%d%d%d%d%d%d%d%d%d%d%d\n", id, v[0], v[1], v[2], v[3], v[4], v[5], v[6], v[7], v[8], v[9], v[10], v[11],
				 v[12], v[13], v[14], v[15]);
		fflush(stdout);*/
		return 1;
	}
	return 0;
}