Cod sursa(job #998196)

Utilizator radustn92Radu Stancu radustn92 Data 16 septembrie 2013 03:14:13
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.98 kb
#include <cstdio>
#include <vector>
#include <queue>
#define NMAX 100005
#define pb push_back
using namespace std;
int n, m, start;
typedef  vector <int> vi;
vi A[NMAX];

int main()
{
    freopen("bfs.in", "r", stdin);
    freopen("bfs.out", "w", stdout);
    scanf("%d%d%d", &n, &m, &start);
    int i, x, y;
    for (i = 1; i <= m; i++)
    {
        scanf("%d%d", &x, &y);
        A[x].pb(y); 
    }
    
    vi d(n + 1, NMAX);
    d[start] = 0;
    
    queue <int> Q;
    Q.push(start);
    
    while (!Q.empty())
    {
        x = Q.front();
        Q.pop();
        for (i = 0; i < (int)A[x].size(); i++)
        {
            y = A[x][i];
            if (d[y] > d[x] + 1)
            {
                d[y] = d[x] + 1;
                Q.push(y);
            }
        }
    }
    
    for (i = 1; i <= n; i++)
        if (d[i] == NMAX)
            printf("-1 ");
        else
            printf("%d ", d[i]);
    printf("\n");
    return 0;
}