Cod sursa(job #2261215)

Utilizator BlkAlexAlex Negru BlkAlex Data 16 octombrie 2018 08:13:38
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.96 kb
#include <bits/stdc++.h>
#define NMAX 100100
#define MMAX 1000100

using namespace std;

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

vector <int> v[NMAX];
bool viz[NMAX];
int n, m, s;
int sol[MMAX];

void bfs (int node){
    int i, newnode;
    queue <int> q;
    q.push(node);
    viz[node]=true;
    while(!q.empty()){
        newnode=q.front();
        q.pop();
        for(i=0; i<v[newnode].size(); i++){
            int lastnode=v[newnode][i];
            if (viz[lastnode]==false){
                viz[lastnode]=true;
                sol[lastnode]=sol[newnode]+1;
                q.push(lastnode);
            }
        }
    }
}

int main()
{
    ios_base::sync_with_stdio(false);
    int i, x, y;
    f>>n>>m>>s;
    for (i=1; i<=m; i++){
        f>>x>>y;
        v[x].push_back(y);
    }
    viz[s]=1;
    bfs(s);
    for(i=1; i<=n; i++){
        if(viz[i]==0) g<<"-1 ";
        else g<<sol[i]<<" ";
    }
    return 0;
}