Cod sursa(job #775141)

Utilizator cameleonGeorgescu Dan cameleon Data 7 august 2012 13:18:00
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;
#define NMAX 100010
ifstream f("bfs.in");
ofstream g("bfs.out");
vector <int> a[NMAX];
int n,m,s,viz[NMAX];
void cit()
{
	f>>n>>m>>s;
	for(int i=1;i<=m;++i)
	{
		int x,y;
		f>>x>>y;
		a[x].push_back(y);
	}
}

void bfs(int s)
{
	queue <int> q;
	vector<int> :: iterator it;
	q.push(s);viz[s]=1;
	while(!q.empty())
	{
		int x=q.front();
		q.pop();
		for(it=a[x].begin();a[x].end()!=it;++it)
			if(viz[*it]==0)
			{
				viz[*it]=viz[x]+1;
				q.push(*it);
			}
	}
}
int main()
{
	cit();
	bfs(s);
	for(int i=1;i<=n;i++)
		g<<viz[i]-1<<' ';
	return 0;
}