Cod sursa(job #1808334)

Utilizator triscacezarTrisca Vicol Cezar triscacezar Data 17 noiembrie 2016 16:59:43
Problema BFS - Parcurgere in latime Scor 20
Compilator cpp Status done
Runda Arhiva educationala Marime 0.82 kb
#include <fstream>
#include <vector>
#include <deque>

using namespace std;
ifstream f("bfs.in");
ofstream g("bfs.out");
vector<int> v[100010];
deque<pair<int,int> > sol;
int n,m,i,s,x,y,rez[100010],viz[100010];
int main()
{
    f>>n>>m>>s;
    for(i=1;i<=m;i++)
    {
        f>>x>>y;
        v[x].push_back(y);
    }
    for(i=1;i<=n;i++)
        rez[i]=n+1;
    sol.push_front(make_pair(s,0));
    while(sol.size())
    {
        viz[sol.front().first]=1;
        rez[sol.front().first]=sol.front().second;
        for(auto it:v[sol.front().first])
            if(viz[it]==0)
                sol.push_back(make_pair(it,sol.front().second+1));
        sol.pop_front();
    }
    for(i=1;i<=n;i++)
        if(rez[i]==n+1)
            g<<-1<<' ';
        else
            g<<rez[i]<<' ';
    return 0;
}