Cod sursa(job #1094498)

Utilizator obidanDan Ganea obidan Data 29 ianuarie 2014 14:58:51
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1 kb
#include <stdio.h>
#include <vector>
#include <queue>
#define NMax 100002
using namespace std;
vector<int> G[NMax];
vector<int>::iterator it;
int n,m,s;
int dist[NMax];

void read()
{
    int x,y,i;
    freopen("bfs.in","r",stdin);
    scanf("%d%d%d",&n,&m,&s);
    for(i=1;i<=m;i++)
    {
        scanf("%d%d",&x,&y);
        G[x].push_back(y);
    }
    fclose(stdin);
}
void bfs()
{
    int from;
    queue<int> Q;
    Q.push(s);
    dist[s]=1;
    while(!Q.empty())
    {
        from=Q.front();
        Q.pop();
        for(it=G[from].begin();it!=G[from].end();it++)
        {
            if(!dist[*it])
                    {
                        dist[*it]=dist[from]+1;
                        Q.push(*it);
                    }
        }
    }
}
void afisare()
{
    freopen("bfs.out","w",stdout);
    for(int i=1;i<=n;i++)
    {
        printf("%d ",dist[i]-1);
    }

    fclose(stdout);
}
int main()
{
    read();
    bfs();
    afisare();
    return 0;
}