Cod sursa(job #2790238)

Utilizator Radu_TudorRadu Tudor Radu_Tudor Data 28 octombrie 2021 17:18:37
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.01 kb
#include <fstream>
#include <iostream>
#include <vector>
#include <queue>

using namespace std;

ifstream fin("bfs.in");
ofstream fout("bfs.out");

const int N_LIM = 100005;

int n, m, nodStart;
int distanta[N_LIM];

vector<int> muchii[N_LIM];
queue<int> coada;

void citire()
{
	fin >> n >> m >> nodStart;

	for (int i = 1; i <= m; i++)
	{
		int x, y;
		fin >> x >> y;

		muchii[x].push_back(y);
	}
}

void bfs()
{
	int nod, vecin;

	while (!coada.empty())
	{
		nod = coada.front();
		coada.pop();

		for (unsigned int i = 0; i < muchii[nod].size(); i++)
		{
			vecin = muchii[nod][i];

			if (distanta[vecin] == -1)
				coada.push(vecin), distanta[vecin] = distanta[nod] + 1;
		}
	}
}

void rezolvare()
{
	for (int i = 1; i <= n; i++)
		distanta[i] = -1;

	distanta[nodStart] = 0;
	coada.push(nodStart);

	bfs();

	for (int i = 1; i <= n; i++)
		fout << distanta[i] << " ";
}

int main()
{
	citire();
	rezolvare();

	fin.close();
	fout.close();
	return 0;
}