Cod sursa(job #1756893)

Utilizator GinguIonutGinguIonut GinguIonut Data 13 septembrie 2016 20:54:34
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.99 kb
#include <fstream>
#include <vector>
#include <queue>

#define nMax 100001
#define mMax 1000001
#define pb push_back
#define mkp make_pair

using namespace std;

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

int n, m, S;
int dist[nMax];
vector<int> G[nMax];
queue<int> Q;

void read()
{
    int a, b;
    fin>>n>>m>>S;

    for(int i=1; i<=m; i++)
    {
        fin>>a>>b;
        G[a].pb(b);
    }
}

void solve()
{
    for(int i=1; i<=n; i++)
        dist[i]=-1;

    dist[S]=0;

    for(Q.push(S); !Q.empty(); Q.pop())
    {
        int node=Q.front();

        for(vector<int>::iterator it=G[node].begin(); it!=G[node].end(); it++)
        {
            int fiu=*it;

            if(dist[fiu]==-1)
            {
                dist[fiu]=dist[node]+1;
                Q.push(fiu);
            }
        }
    }

}

void write()
{
    for(int i=1; i<=n; i++)
        fout<<dist[i]<<" ";
}
int main()
{
    read();
    solve();
    write();
}