Cod sursa(job #501894)

Utilizator perticas_catalinperticas catalin perticas_catalin Data 16 noiembrie 2010 22:53:36
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.91 kb
#include <iostream>
#include <string>
#include <vector>
#include <queue>

using namespace std;

#define NM 100005
#define inf 1000000000

int N, M, S, dmin[NM];

vector <int> G[NM];

bool viz[NM];

int main()
{
	freopen ("bfs.in", "r", stdin);
	freopen ("bfs.out", "w", stdout);
	
	scanf ("%d %d %d", &N, &M, &S);
	
	for (int i = 1; i <= M; ++i)
	{
		int a, b;
		
		scanf ("%d %d", &a, &b);
		
		G[a].push_back(b);
	}	
	
	queue <int> Q;
	
	for (int i = 1; i <= N; ++i) dmin[i] = inf;
	
	dmin[S] = 0;
	Q.push(S);
	viz[S] = 1;
	
	while (!Q.empty())
	{
		int nod = Q.front();
		Q.pop();
		
		for (int i = 0; i < G[nod].size(); ++i)
		{
			int nnod = G[nod][i];
			if (viz[nnod]) continue;
			
			dmin[nnod] = dmin[nod] + 1;
			Q.push(nnod);
			viz[nnod] = 1;
		}	
	}	
	
	for (int i = 1; i <= N; ++i) 
		if (!viz[i]) printf ("-1 ");
		else printf ("%d ", dmin[i]);
	
	return 0;
}