Cod sursa(job #1612559)

Utilizator SlevySlevoaca Stefan-Gabriel Slevy Data 24 februarie 2016 22:08:08
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.15 kb
#include <fstream>
#include <vector>
#include <bitset>
#include <queue>

using namespace std;

int n,m,s;
const int NMAX = 100010;
vector<int> muchii[NMAX];
vector<int>::iterator it;
queue<int> coada;
int *mark;
bitset<NMAX> viz;

void citire()
{
    scanf("%d",&n);
    scanf("%d",&m);
    scanf("%d",&s);
    int x,y;
    for(int i=1;i<=m;i++)
    {
        scanf("%d",&x);
        scanf("%d",&y);
        muchii[x].push_back(y);
    }
    fclose(stdin);
}

void parcurgere()
{
    coada.push(s);
    viz.set(s);
    while(!coada.empty())
    {
        int x = coada.front();
        for(it = muchii[x].begin();it<muchii[x].end();it++)
            if(!viz.test(*it))
        {
            coada.push(*it);
            mark[*it] = mark[x] + 1;
            viz.set(*it);
        }
    coada.pop();
    }
}

int main()
{
    freopen("bfs.in","r",stdin);
    freopen("bfs.out","w",stdout);
    citire();
    mark = new int[n+1];
    for(int i=1;i<=n;i++)
    mark[i] = (i==s) ? 0: -1;
    parcurgere();
    for(int i=1;i<=n;i++)
       printf("%d ",mark[i]);
    fclose(stdout);
    delete[] mark;
    return 0;
}