Cod sursa(job #2791290)

Utilizator sireanu_vladSireanu Vlad sireanu_vlad Data 30 octombrie 2021 12:36:47
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.62 kb
#include <fstream>
#include <vector>
#include <queue>
using namespace std;

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

int n, m, S, v[100001];
vector<int> g[100001];
queue<int> q;

void read()
{
	in >> n >> m >> S;
	int x, y;
	for(int i = 0; i < m; ++i)
		in >> x >> y, g[x].push_back(y);
}

void bfs(int s)
{
	q.push(s), v[s] = 1;
	while(!q.empty())
	{
		for(auto i : g[q.front()])
			if(!v[i]) q.push(i), v[i] = v[q.front()] + 1;
		q.pop();
	}
}

void afis()
{
	for(int i = 1; i <= n; ++i)
		out << (v[i] ? v[i]-1 : -1) << ' ';
}

int main()
{
	read();
	bfs(S);
	afis();
	return 0;
}