Cod sursa(job #2720843)

Utilizator FrostfireMagirescu Tudor Frostfire Data 11 martie 2021 12:29:17
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.75 kb
#include <iostream>
#include <fstream>
#include <queue>
#define NMAX 100000

using namespace std;

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

int n, m, s, dist[NMAX+10], viz[NMAX+10];
queue <int> Q;
vector <int> nod[NMAX+10];

void bfs()
{	viz[s] = 1;
	Q.push(s);
	while(!Q.empty())
		{	int x = Q.front();
			Q.pop();
			for(auto u : nod[x])
				if(!viz[u])
					{	viz[u] = 1;
						dist[u] = dist[x] + 1;
						Q.push(u);
					}
		}
}

int main()
{
	fin >> n >> m >> s;
	for(int i=1; i<=m; i++)
		{	int nod1, nod2;
			fin >> nod1 >> nod2;
			nod[nod1].push_back(nod2);
		}
	for(int i=1; i<=n; i++)
		dist[i] = -1;
	dist[s] = 0;
	bfs();
	for(int i=1; i<=n; i++)
		fout << dist[i] << ' ';
	fout << '\n';
	return 0;
}