Cod sursa(job #2193805)

Utilizator seba_elementsDeaconu Sebastian seba_elements Data 11 aprilie 2018 16:14:57
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.76 kb
#include <fstream>
#include <vector>
#include <algorithm>
#include <queue>
using namespace std;
ifstream fin("bfs.in");
ofstream fout("bfs.out");
const int NMAX=100000;
vector <int> G[NMAX+5],d;
vector <bool> viz;
int n;
queue<int>q;
void bfs(int u)
{
	int v,j;
	viz.assign(n+1,0);
	d.assign(n+1,0);
	q.push(u);
	viz[u]=1;
	while(!q.empty())
	{
		u=q.front();q.pop();
		for(j=0;j<G[u].size();j++)
		{
			v=G[u][j];
			if(viz[v]==0)
			{
				viz[v]=1;
				d[v]=d[u]+1;
				q.push(v);
			}
		}
	}
}
int main()
{
    int m,s,u,v,i;
    fin>>n>>m>>s;
    for(i=1;i<=m;i++)
	{
		fin>>u>>v;
		G[u].push_back(v);
	}
	bfs(s);
	for(i=1;i<=n;i++)
		if(d[i]==0&&i!=s)
			d[i]=-1;
	for(i=1;i<=n;i++)
		fout<<d[i]<<" ";
    return 0;
}