Cod sursa(job #677257)

Utilizator grigoritaiulianDeactivated Profile grigoritaiulian Data 9 februarie 2012 22:37:01
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.31 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <deque>
#include <queue>

#define INFINIT 0X3f3f3f
#define MAXIM_NODURI 100001

using namespace std;

fstream fin("bfs.in", ios::in), fout("bfs.out", ios::out);

int noduri, muchii, nod_de_inceput, nod_curent;
int vizitat[MAXIM_NODURI], arc_minim[MAXIM_NODURI];

vector < int > graf[MAXIM_NODURI];
vector < int > :: iterator it;

queue < int > coada;

inline void read()
{
	int x, y;
	fin >> noduri >> muchii >> nod_de_inceput;
	while(fin >> x >> y)
	{
		graf[x].push_back(y);
	}
	fin.close();
}

inline void parcurgere_in_latime(int nod)
{
	vizitat[nod] = 1;
	arc_minim[nod] = 0;
	coada.push(nod);
	while(!coada.empty())
	{
		nod_curent = coada.front();
		for(it = graf[nod_curent].begin(); it != graf[nod_curent].end(); it++)
			if(vizitat[*it] == 0)
			{
			    coada.push(*it);
				vizitat[*it] = 1;
				arc_minim[*it] = arc_minim[nod_curent] + 1;
			}
        coada.pop();
	}
}

int main()
{
    for(int i = 1; i <= noduri; i++)
        arc_minim[i] = -1;
	read();
	parcurgere_in_latime(nod_de_inceput);
	for(int i = 1; i <= noduri; i++)
        if(arc_minim[i] == 0 && i != nod_de_inceput)
            fout << -1 << ' ';
        else
            fout << arc_minim[i] << ' ';
    fout.close();
	return 0;
}