Cod sursa(job #1051959)

Utilizator vasandANDREI POP vasand Data 10 decembrie 2013 19:17:18
Problema BFS - Parcurgere in latime Scor 70
Compilator cpp Status done
Runda Arhiva educationala Marime 0.96 kb
# include <iostream>
# include <fstream>
# include <vector>
# include <queue>
# include <string.h>
# define nmax 100000
using namespace std;

ifstream f("bfs.in");
ofstream g("bfs.out");

vector <int> v[nmax];
queue <int> coada;
int n,m,s,valid[nmax];

int main()
{
    f>>n>>m>>s;
    int i,x,y;
    for(i=1; i<=m; i++)
    {
        f>>x>>y;
        v[x].push_back(y);
    }

    coada.push(s);
    int cate=0;
    valid[s]=0;
    while(!coada.empty())
    {
        cate+=1;
        for(i=0; i<v[coada.front()].size(); i++)
        {
            if(valid[v[coada.front()][i]]==0 && v[coada.front()][i]!=s)
            {
                coada.push(v[coada.front()][i]);
                valid[v[coada.front()][i]]=valid[coada.front()]+1;
            }
        }
        coada.pop();
    }

    for(i=1; i<=n; i++)
        if(valid[i]!=0 || i==s)
            g<<valid[i]<<" ";
        else
            g<<"-1 ";

    return 0;
}