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Cod sursa(job #640707)

Utilizator yamahaFMI Maria Stoica yamaha Data 26 noiembrie 2011 13:03:34
Problema BFS - Parcurgere in latime Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 0.83 kb
#include <stdio.h>
#include <vector>

using namespace std;

#define maxn 100010

int N, M, L, Start;
vector <int> A[maxn];
int G[maxn], S[maxn], Cost[maxn];

void BFS(int);

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;
}

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++)
		for (j = 0; j < G[S[i]]; j++)
			if (Cost[A[S[i]][j]] == -1)
			{
				S[++L] = A[S[i]][j];
				Cost[S[L]] = Cost[S[i]] + 1;
			}
}