Cod sursa(job #1778479)

Utilizator stefan_creastaStefan Creasta stefan_creasta Data 13 octombrie 2016 20:39:22
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.01 kb
#include <cstdio>
#include <algorithm>
#include <queue>
#include <vector>
using namespace std;
const int N = 100005;
const int INF = 2000000000;
vector <int> v[N];
queue <int> q;
int d[N];
void bfs()
{
    int poz;
    while(q.size())
    {
        poz = q.front();
        q.pop();
        for(auto it : v[poz])
        {
            if(d[it] > d[poz] + 1)
            {
                d[it] = d[poz] + 1;
                q.push(it);
            }
        }
    }
}

int main()
{
    int n, m, i, x, y, nr;
    freopen("bfs.in","r",stdin);
    freopen("bfs.out","w",stdout);
    scanf("%d%d%d", &n, &m, &nr);
    for(i = 1;i <= m; ++i)
    {
        scanf("%d%d", &x, &y);
        v[x].push_back(y);
    }
    fill(d + 0 , d + N - 1 , INF);
    d[nr] = 0;
    q.push(nr);
    bfs();
    for(i = 1;i <= n; ++i)
    {
        if(d[i] == INF){
            printf("-1 ");
        }
        else{
            printf("%d ",d[i]);
        }
    }
    printf("\n");
    return 0;
}