Cod sursa(job #2144304)

Utilizator alisavaAlin Sava alisava Data 26 februarie 2018 17:45:20
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.85 kb
#include <bits/stdc++.h>
#define infinit 1000000000

using namespace std;

ifstream fin("bfs.in");
ofstream fout("bfs.out");

vector<int>v[100005];
int a[100005];
queue<int>q;
int n,m,s;
int main()
{
    int x,y;
    fin>>n>>m>>s;
    for(int i=1;i<=m;i++)
    {
        fin>>x>>y;
        v[x].push_back(y);
       // v[y].push_back(x);
    }
    q.push(s);
    for(int i=1;i<=n;i++)
        a[i]=infinit;
    a[s]=0;
    while(!q.empty())
    {
        x=q.front();
        q.pop();
        for(int i=0;i<v[x].size();i++)
        {
            if(a[v[x][i]]>a[x]+1)
            {
                a[v[x][i]]=a[x]+1;
                q.push(v[x][i]);
            }
        }
    }
    for(int i=1;i<=n;i++)
    {
        if(a[i]==infinit) fout<<"-1 ";
        else fout<<a[i]<<" ";
    }
    fout<<"\n";
    return 0;
}