Cod sursa(job #1455565)

Utilizator DenisacheDenis Ehorovici Denisache Data 28 iunie 2015 14:26:45
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.35 kb
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <vector>
#include <string>
#include <iostream>
#include <list>
#include <queue>
#include <set>
#include <unordered_map>
#include <functional>
//#include <conio.h>
#define pb push_back
#define mp make_pair
#define MOD 9901
#define newl printf("\n")
#define NMAX 100005
#define nst (nod<<1)
#define ndr (nst+1)
#define vi vector<int>
#define pii pair<int,int>
#define fi first
#define se second
using namespace std;
int n,m,S,D[NMAX];
vi G[NMAX];
queue <int> Q;
bool used[NMAX];
const int INF = (1<<30);
void BFS(int start)
{
    for (int i=1;i<=n;i++)
        D[i]=INF;
    D[start]=0;
    Q.push(start);
    while (!Q.empty())
    {
        int nod=Q.front();
        Q.pop();
        for (vi::iterator it=G[nod].begin();it!=G[nod].end();it++)
        {
            if (!used[*it] && D[nod]+1<D[*it])
            {
                D[*it]=D[nod]+1;
                used[*it]=true;
                Q.push(*it);
            }
        }
    }
    for (int i=1;i<=n;i++)
        printf("%d ",(D[i]==INF)?(-1):D[i]);
}
int main()
{
    freopen("bfs.in","r",stdin);
    freopen("bfs.out","w",stdout);
    scanf("%d %d %d",&n,&m,&S);
    int a,b;
    while (m--)
    {
        scanf("%d %d",&a,&b);
        G[a].pb(b);
    }
    BFS(S);
    return 0;
}