Cod sursa(job #779584)

Utilizator stefanzzzStefan Popa stefanzzz Data 18 august 2012 09:24:09
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.78 kb
#include <fstream>
#include <vector>
#include <queue>
#define MAXN 100005
using namespace std;
ifstream f("bfs.in");
ofstream g("bfs.out");

int n,m,s,x,y,d,dist[MAXN];
vector<int> G[MAXN];
queue<int> q;
bool uz[MAXN];

int main()
{
    int i;
    f>>n>>m>>s;
    for(i=1;i<=m;i++){
        f>>x>>y;
        G[x].push_back(y);}
    uz[s]=1;
    q.push(s);
    while(!q.empty()){
        x=q.front();
        q.pop();
        d=dist[x];
        for(i=0;i<G[x].size();i++)
            if(!uz[G[x][i]]){
                uz[G[x][i]]=1;
                dist[G[x][i]]=d+1;
                q.push(G[x][i]);}}
    for(i=1;i<=n;i++){
        if(uz[i])
            g<<dist[i]<<' ';
        else
            g<<"-1 ";}
    f.close();
    g.close();
    return 0;
}