Cod sursa(job #2065791)

Utilizator bent_larsenSturzu Antonio-Gabriel bent_larsen Data 14 noiembrie 2017 10:50:08
Problema BFS - Parcurgere in latime Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 0.98 kb
#include <fstream>
#include <vector>
#include <queue>
using namespace std;

vector<vector<int> > adj;
const int nmax = 100005;
bool viz[nmax];

vector<int> bfs (int S, int N)
{
	vector<int> dist;
	dist.resize(N);
	
	queue<int> q;
	q.push(S);
	viz[S] = true;
	dist[S] = 0;
	
	for(int i = 0;i < N;++i)
	{
		dist[i] = -1;
	}
	while(!q.empty())
	{
		int nod = q.front();
		q.pop();
		
		for(int i = 0;i < (int) adj[nod].size();++i)
		{
			int neigh = adj[nod][i];
			if(!viz[neigh])
			{
				dist[neigh] = dist[nod] + 1;
				viz[neigh] = true;
				q.push(neigh);
			}
		}
	}
	return dist;
}

int main()
{
	ifstream in("bfs.in");
	ofstream out("bfs.out");
	
	int N, M, S;
	in >> N >> M >> S;
	
	adj.resize(N);
	for(int i = 0;i < M;++i)
	{
		int x, y;
		in >> x >> y;
		
		--x, --y;
		adj[x].push_back(y);
	}
	
	vector<int> dist = bfs (S, N);
	for(int i = 0;i < (int) dist.size();++i)
	{
		out << dist[i] <<" ";
	}
	in.close();
	out.close();
}