Cod sursa(job #673870)

Utilizator nutipasa16Macovei Claudiu nutipasa16 Data 5 februarie 2012 00:15:31
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.74 kb
#include <fstream>
#include <string.h>
#include <vector>
#include <deque>
#define Nmax 100009
using namespace std;
ifstream f("bfs.in");
ofstream g("bfs.out");
int nod,x,y,n,m,s,nr[Nmax];
vector < int > a[Nmax];
deque < int > Q;
vector < int >::iterator it;
void BFS()
	{Q.push_back(s);
    while (!Q.empty())
		{nod=Q.front();
         Q.pop_front();
		 for (it=a[nod].begin();it!=a[nod].end();it++)
				if (nr[*it]==-1) {nr[*it]=nr[nod]+1;
								  Q.push_back(*it);
								  }
		}
	}
int main()
	{f>>n>>m>>s;
    for (register int i=1;i<=m;++i)
		{f>>x>>y;
         a[x].push_back(y);
		}
    memset(nr,-1,sizeof(nr));
    nr[s]=0;
    BFS();
    for (register int i=1;i<=n;++i)g<<nr[i]<<" ";
	g<<'\n';
	return false;
}