Cod sursa(job #739256)

Utilizator paunmatei7FMI Paun Matei paunmatei7 Data 22 aprilie 2012 15:35:02
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.92 kb
#include <cstdio>
#include <vector>
#include<cstring>
#define maxn 100010
using namespace std;
int N, M, L, Start;
vector <int> A[maxn];
int G[maxn], S[maxn], Cost[maxn];
void BFS(int nod)
{
	int i, j;
	memset(Cost, -1, sizeof(Cost));
	L = 1;
	Cost[nod] = 0;
	S[L] = nod;
	for (i = 1; i <= L; i++)	//	Elimin pe rand nodurile din coada
		for (j = 0; j < G[S[i]]; j++)	//	Parcurg vecinii nodului ce urmeaza sa fie eliminat
			if (Cost[A[S[i]][j]] == -1)
			{
				//	Adaug vecinii nevizitati in coada si le calculez distanta
				S[++L] = A[S[i]][j];
				Cost[S[L]] = Cost[S[i]] + 1;
			}
}	
int main()
{
	freopen("bfs.in", "r", stdin);
	freopen("bfs.out", "w", stdout);
	int i, x, y;
	scanf("%d %d %d ", &N, &M, &Start);
	for (i = 1; i <= M; i++) 
	{
		scanf("%d %d ", &x, &y);
		A[x].push_back(y);
	}
	for (i = 1; i <= N; i++) 
		G[i] = A[i].size();
	BFS(Start);
	for (i = 1; i <= N; i++) 
		printf("%d ", Cost[i]);
	printf("\n");
	return 0;
}