Cod sursa(job #1479698)

Utilizator elevenstrArina Raileanu elevenstr Data 31 august 2015 22:46:50
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.85 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <bitset>
#include <map>
#include <queue>
//http://www.infoarena.ro/problema/bfs
using namespace std;
#define MAX 100020
int d[MAX];
int n,m,s;
ifstream in("bfs.in");
ofstream out("bfs.out");
bitset <MAX> viz;
vector <int> v[MAX];
vector <int> ::iterator it;
queue <int> Q;
int main()
{   int k=0;
    int i,x,y;
    in>>n>>m>>s;
    for(i=1;i<=m;i++)
    {
        in>>x>>y;
        v[x].push_back(y);

    }
    Q.push(s);
    d[s]=1;
    while(!Q.empty())
    {   x=Q.front();
        Q.pop();
        for(it=v[x].begin();it!=v[x].end();++it)
            {if(d[*it]==0||d[*it]>d[x]+1) {
                    d[*it]=d[x]+1;
                Q.push(*it);}}
    }
    for(i=1;i<=n;i++)
       if(d[i]==0)out<<-1<<" ";
       else out<<d[i]-1<<" ";



    return 0;
}