Cod sursa(job #1501580)

Utilizator refugiatBoni Daniel Stefan refugiat Data 13 octombrie 2015 17:31:22
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.94 kb
#include<fstream>
#include<iostream>
#include<cstring>
#include<queue>
#include<vector>
using namespace std;
const int PCT=100003;
vector<int> v[PCT];
int cost[PCT];
queue<int> q;
void bfs(int s)
{
    q.push(s);
    cost[s]=0;
    int poz,i,n;
    while(!q.empty())
    {
        poz=q.front();
        q.pop();
        n=v[poz].size();
        for(i=0;i<n;++i)
        {
            if(cost[v[poz][i]]==-1)
            {
                cost[v[poz][i]]=cost[poz]+1;
                q.push(v[poz][i]);
            }
        }
    }
}
int main()
{
    ifstream si;
    si.open("bfs.in");
    ofstream so;
    so.open("bfs.out");
    int n,m,s;
    si>>n>>m>>s;
    int i,a,b;
    for(i=0;i<m;++i)
    {
        si>>a>>b;
        v[a].push_back(b);
    }
    memset(cost,-1,sizeof cost);
    bfs(s);
    for(i=1;i<=n;++i)
        so<<cost[i]<<' ';
    so<<'\n';
    si.close();
    so.close();
    return 0;
}