Cod sursa(job #2212762)

Utilizator rockah0licCalin David rockah0lic Data 14 iunie 2018 18:47:42
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.74 kb
#include <iostream>
#include <vector>
#include <fstream>
using namespace std;

ifstream in("bfs.in");
ofstream out("bfs.out");

const int N=100001;
vector<int> a[N];
int n,m,x0,q[N],d[N];

void citire(){
    in>>n>>m>>x0;
    int x,y;
    for(int i=0;i<m;i++){
        in>>x>>y;
        a[x].push_back(y);
    }
    in.close();
}

void bfs(){
    int x,y,st=0,dr=-1;
    for(int i=1;i<=n;i++)
        d[i]=-1;
    d[x0]=0;
    q[++dr]=x0;
    while(st<=dr){
        x=q[st++];
        for(int i=0;i<a[x].size();i++){
            y=a[x][i];
            if(d[y]==-1){
                d[y]=1+d[x];
                q[++dr]=y;
            }
        }
    }
}

int main()
{
    citire();
    bfs();
    for(int i=1;i<=n;i++)
        out<<d[i]<<" ";
    return 0;
}