Cod sursa(job #800009)

Utilizator andy_vamosRezus Andrei andy_vamos Data 20 octombrie 2012 15:44:25
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.65 kb
#include<fstream>
#include<vector>
#include<queue>
using namespace std;
ifstream f("bfs.in");
ofstream g("bfs.out");
int i,j,n,m,s,x,y,d[100010],viz[100010];
vector<int> a[100010];
queue<int> q;
void det()
{
	int i,x;
	q.push(s);
	d[s]=0;
	while(!q.empty())
	{
		x=q.front();
		for(i=0;i<a[x].size();++i)
			if(!viz[a[x][i]]&&d[a[x][i]]>d[x]+1)
			{
				viz[a[x][i]]=1;
				d[a[x][i]]=d[x]+1;
				q.push(a[x][i]);
			}
			q.pop();
	}
}
int main()
{
f>>n>>m>>s;
	for(i=1;i<=n;++i)
		d[i]=100000001,viz[i]=0;
	for(i=1;i<=m;++i)
	{
		f>>x>>y;
		a[x].push_back(y);
	}
	det();
	for(i=1;i<=n;++i)
		if(d[i]==100000001)
			g<<-1<<" ";
		else
			g<<d[i]<<" ";
	return 0;
}