Cod sursa(job #1388823)

Utilizator AlexandraaaaMereu Alexandra Alexandraaaa Data 15 martie 2015 19:08:53
Problema BFS - Parcurgere in latime Scor 60
Compilator cpp Status done
Runda Arhiva educationala Marime 0.9 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#define max 100010
using namespace std;

vector <int> G[max];
void bf(int v, int s, int nr[]) {
	int i, j, grad[max];
	for (i = 1; i <= v; i++) {
		grad[i] = G[i].size();
	}
	queue <int> Coada;
	nr[s]++;
	for (i = 0; i < grad[s]; i++)
		if (nr[G[s][i]] == -1) {
			Coada.push(G[s][i]);
			nr[G[s][i]] = 1;
		}
	while (!Coada.empty()) {
		j = Coada.front();
		Coada.pop();
		for (i = 0; i < grad[j]; i++)
			if (nr[G[j][i]] == -1) {
				Coada.push(G[j][i]);
				nr[G[j][i]] = nr[j] +
					1;
			}
	}
}

int main()
{
	int i, v, e, x, y, s, nr[max];
	ifstream f("bfs.in");
	ofstream g("bfs.out");
	f >> v >> e >> s;
	for (i = 1; i <= e; i++) {
		f >> x >> y;
		G[x].push_back(y);
		nr[i] = -1;
	}
	bf(v, s, nr);
	for (i = 1; i <= v; i++)
		g << nr[i] << " ";
	f.close();
	g.close();
	return 0;
}