Cod sursa(job #1108784)

Utilizator PlatonPlaton Vlad Platon Data 16 februarie 2014 13:08:13
Problema BFS - Parcurgere in latime Scor 70
Compilator cpp Status done
Runda Arhiva educationala Marime 1.04 kb
#include <stdio.h>
#include <vector>
#include <queue>

#define print(a) printf("%d ", a)
#define scan(a) scanf("%d", &a)

#define maxn 100000

using std::vector;
using std::queue;

int n, m, s, d[maxn];
vector<int> G[maxn];
queue<int> q;

void citire()
{
    freopen("bfs.in", "r", stdin);

    int a,b;
    scan(n); scan(m); scan(s);
    for(int i=0; i<m; i++)
    {
        scan(a); scan(b);
        G[a].push_back(b);
    }
}

void afisare()
{
	freopen("bfs.out", "w", stdout);

    for(int i=1;i<=n;i++)
    {
        print(d[i]);
    }
    printf("\n");
}

void bfs(int x)
{
    q.push(x);
    d[x] =0;
    while(!q.empty())
    {
        int p = q.front();
        q.pop();
        for(int i=0;i<G[p].size();i++)
        {
            int c = G[p][i];
            if(d[c]==-1)
            {
                d[c] = d[p]+1;
                q.push(c);
            }
        }
    }
}

int main()
{
    citire();

    for(int i=1;i<=n;i++)
	{
		d[i]=-1;
	}

    bfs(s);

    afisare();
}