Cod sursa(job #634612)

Utilizator JBaccountCatalin JBaccount Data 16 noiembrie 2011 19:25:00
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.9 kb
#include <iostream>
#include <cstdio>
#include <string>
#include <vector>

using namespace std;

#define inf 1000000000
#define NM 100005

vector <int> G[NM];
int N, M, coada[NM], C[NM];

int main()
{
	int s, st = 0, dr = -1;
	
	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);
		//G[b].push_back(a);
	}	
	
	for (int i = 1; i <= N; ++i) C[i] = inf;
	coada[++dr] = s;
	C[s] = 0;
	
	while (st <= dr)
	{
		int nod = coada[st];
		++st;
		
		for (int i = 0; i < G[nod].size(); ++i)
		{
			int nnod = G[nod][i];
			
			if (C[nnod] == inf)
			{
				C[nnod] = C[nod] + 1;
				coada[++dr] = nnod;
			}	
		}	
	}	
	
	for (int i = 1; i <= N; ++i) 
		if (C[i] == inf) printf ("-1 "); 
		else printf ("%d ", C[i]);
	
	return 0;
}