Cod sursa(job #640804)

Utilizator AndreiRSStatescu Andrei Rares AndreiRS Data 26 noiembrie 2011 15:31:42
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.89 kb
#include <stdio.h>
#include <list>
#include <deque>
using namespace std;

const int DIM = 100005;
int N, M, dst[DIM], viz[DIM], C[DIM], U[DIM], T[DIM*11], V[DIM*11], S, K;

void bfs ()
{
	int p = 0, u = 0, n, f;
	C[0] = S;
	viz[S] = 1;
	
	while (p <= u)
	{
		n = C[p];
		for (int i = n-1; T[i] != 0; i = T[i])
		{
			f = V[i];
			if (viz[f] == 0)
			{
				C[++u] = f;
				viz[f] = 1;
				dst[f] = dst[n] + 1;
			}
		}
		p++;
	}	
}

int main ()
{
	freopen ("bfs.in", "r", stdin);
	freopen ("bfs.out", "w", stdout);
	
	scanf ("%d%d%d", &N, &M, &S);
	for (int i = 1; i <= N; i++)
		U[i] = i-1;
	K = N;
	for (int i = 0, a, b; i < M; i++)
	{
		scanf ("%d%d", &a, &b);
		V[U[a]] = b;
		T[U[a]] = K;
		U[a] = K++;
	}
	
	bfs ();
	
	for (int i = 1; i <= N; i++)
		if (dst[i] == 0 && i != S)
			printf ("-1 ");
		else
			printf ("%d ", dst[i]);
	return 0;
}