int main(void)
{
char *line;
t_map map;
bzero(&map, sizeof(map));
if (!(map.cells = ht_create(2048)) ||
!(map.list = new_vector(sizeof(char *))) ||
!extract_nb_ants(&map) || map.ants_nb > 1000000)
exit(write(1, "Error\n", 6));
line = NULL;
while (get_next_line(0, &line) == 1)
{
write(1, line, ft_strlen(line));
write(1, "\n", 1);
if (!analyze_line(line, &map))
break ;
free(line);
}
write(1, "\n", 1);
if (map.start && map.end)
solve_master(&map);
else
write(1, "Error\n", 6);
return (1);
}
/*
invoked by the master to solve find all solutions
of the first k columns
solutions are put onto the jobs queue
*/
void solve_master(int col, int *hist)
{
if (col == K) {
enqueue(jobs, hist); //found a k length solution, throw it on the queue
return;
}
# define attack(i, j) (hist[j] == i || abs(hist[j] - i) == col - j)
for (int i = 0, j = 0; i < N; i++) { //for each row
for (j = 0; j < col && !attack(i, j); j++); //if this piece is safe, move to the next column
if (j < col) continue;
hist[col] = i; //this row is safe for the current column
solve_master(col + 1, hist);
}
}
void master()
{
jobs = init_queue();
MPI_Status status;
int hist[N];
solve_master(0, hist);
int processors, rank;
MPI_Comm_size(MPI_COMM_WORLD, &processors);
int * work;
// send everyone some work!
// keep track of how many nodes received work
int deployed = 0;
for(rank = 1; rank < processors; rank++)
{
if(!is_empty(jobs))
{
work = pop(jobs);
MPI_Send(
work,
K,
MPI_INT,
rank,
WORKTAG,
MPI_COMM_WORLD);
deployed++;
}
}
// now listen for completions and dispatch work until done!
int done[K]; //garbage buffer used to match signature
while(!is_empty(jobs))
{
//receive completion
MPI_Recv(
done, /* message buffer */
1, /* one data item */
MPI_INT, /* of type double real */
MPI_ANY_SOURCE, /* receive from any sender */
MPI_ANY_TAG, /* any type of message */
MPI_COMM_WORLD, /* default communicator */
&status); /* info about the received message */
// send it more work
work = pop(jobs);
MPI_Send(
work,
K,
MPI_INT,
status.MPI_SOURCE,
WORKTAG,
MPI_COMM_WORLD);
}
// work is done, receive outstanding jobs
// receive outstanding jobs only from the number of machines that received work
for(rank = 1; rank <= deployed; rank++)
{
MPI_Recv(
done,
1,
MPI_INT,
MPI_ANY_SOURCE,
MPI_ANY_TAG,
MPI_COMM_WORLD,
&status);
}
// Set the slaves free!
for(rank=1; rank<processors; rank++)
{
MPI_Send(
done,
K,
MPI_INT,
rank,
DIETAG,
MPI_COMM_WORLD);
}
}
