Cod sursa(job #1245507)

Utilizator TheFFOFratila Florin Ovidiu TheFFO Data 19 octombrie 2014 12:49:03
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.87 kb
#include <iostream>
#include <cstdio>
#include <queue>
#include <vector>
using namespace std;
vector<int> g[100005];
queue<int> q;
int v[100005];
void read(int &n,int &m,int &x)
{
    int a,b;
    scanf("%d%d%d",&n,&m,&x);
    for(int i=1;i<=m;++i)
    {
        scanf("%d%d",&a,&b);
        g[a].push_back(b);
    }
}

void bfs()
{
    int n;
    while(!q.empty())
    {
        n=q.front();
        q.pop();
        for(vector<int>::iterator it=g[n].begin();it!=g[n].end();++it)
            if(!v[*it])
            {
                q.push(*it);
                v[*it]=v[n]+1;
            }
    }
}

int main()
{
    freopen("bfs.in","r",stdin);
    freopen("bfs.out","w",stdout);
    int n,m,x;
    read(n,m,x);
    q.push(x);
    v[x]=1;
    bfs();
    for(int i=1;i<=n;++i)
        printf("%d ",v[i]-1);
    printf("\n");
    return 0;
}