Cod sursa(job #1185752)

Utilizator xtreme77Patrick Sava xtreme77 Data 16 mai 2014 19:35:47
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.88 kb
#include <cstdio>
#include <queue>
#include <vector>
const int MAX = 100010;
using namespace std;
vector <int> gr[MAX];
int len[MAX];
void bfs(int st);
int main()
{
    int n,m,st;
    freopen("bfs.in","r",stdin);
    freopen("bfs.out","w",stdout);
    scanf("%d%d%d",&n,&m,&st);
    for(int i=1;i<=m;++i){
        int x,y;
        scanf("%d%d",&x,&y);
        gr[x].push_back(y);
    }
    bfs(st);
    for(int i=1;i<=n;++i){
        if(!len[i])printf("-1 ");
        else printf("%d ",len[i]-1);
    }
    return 0;
}
void bfs(int st){
    queue <int> q;
    len[st]=1;
    q.push(st);
    while(!q.empty()){
        int temp=q.front();
        for(int i=0;i<(int)gr[temp].size();++i){
            if(!len[gr[temp][i]]){
                len[gr[temp][i]]=len[temp]+1;
                q.push(gr[temp][i]);
            }
        }
        q.pop();
    }
}