Cod sursa(job #2168020)

Utilizator andreiutu111Noroc Andrei Mihail andreiutu111 Data 14 martie 2018 09:13:06
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.79 kb
#include<bits/stdc++.h>
using namespace std;
ifstream f("bfs.in");
ofstream g("bfs.out");
int N,M,S,x,y,rez[100001];
bool viz[100001];
vector <int> G[100001];
queue < pair<int,int> > q;
void bfs(int nod){
    q.push(make_pair(nod,0)),viz[nod]=1,rez[nod]=0;
    int nr=0;
    while(!q.empty()){
        y=q.front().first;
        x=q.front().second;
        q.pop();
        for(int i=0;i<G[y].size();++i)
            if(!viz[G[y][i]]){
                viz[G[y][i]]=1;
                rez[G[y][i]]=x+1;
                q.push(make_pair(G[y][i],x+1));
            }
    }
}
int main()
{
    f>>N>>M>>S;
    for(int i=1;i<=N;++i)rez[i]=-1;
    while(M--){
        f>>x>>y;
        G[x].push_back(y);
    }
    bfs(S);
    for(int i=1;i<=N;++i)g<<rez[i]<<' ';
    return 0;
}