Cod sursa(job #1218752)

Utilizator gabrielinelusGabriel-Robert Inelus gabrielinelus Data 12 august 2014 14:22:21
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.94 kb
#include <cstdio>
#include <algorithm>
#include <queue>
#include <vector>
#include <cstring>

#define Nmax 100005

using namespace std;
int N,M,S;
int dist[Nmax];
vector<int> G[Nmax];
queue<int> Q;

void read( void )
{
    scanf("%d%d%d",&N,&M,&S);
    int a,b;
    for(int i =1; i <= M; ++i)
    {
        scanf("%d%d",&a,&b);
        G[a].push_back(b);
    }
}

void BFS(int k)
{
    memset(dist,-1,sizeof(dist));
    dist[k] = 0;
    Q.push(k);
    while(!Q.empty())
    {
        k = Q.front(); Q.pop();
        for(vector<int>::iterator it = G[k].begin(); it != G[k].end(); ++it)
            if(dist[*it] == -1)
            {
                dist[*it] = dist[k] + 1;
                Q.push(*it);
            }
    }
    for(int i = 1; i <= N; ++i)
        printf("%d ",dist[i]);
}

int main()
{
    freopen("bfs.in","r",stdin);
    freopen("bfs.out","w",stdout);

    read();
    BFS(S);

    return 0;
}