Cod sursa(job #1631059)

Utilizator Raluca_Mindrutralucam Raluca_Mindrut Data 5 martie 2016 12:55:42
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.96 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
using namespace std;
ifstream f("bfs.in");
ofstream g("bfs.out");
int n,m,s;
vector<vector<int> > graph;
vector<int>visited;
void bfs(int vertex)
{
    if(vertex<0 || vertex>n-1) return;
    queue <int> q;
    int element,i;
    q.push(vertex);
    visited[vertex]=0;
    while(!q.empty())
    {
        element = q.front();
        for(i=0;i<graph[element].size();i++)
        {
            if(visited[graph[element][i]]==-1)
                {
                    q.push(graph[element][i]);
                    visited[graph[element][i]]=visited[element]+1;
                }

        }q.pop();
    }
}


int main()
{
  f>>n>>m>>s;
  graph.resize(n);
  visited.resize(n,-1);
  int x,y;
  for(int i=0;i<m;i++)
  {
      f>>x>>y;
      x--;
      y--;
      graph[x].push_back(y);
  }
   bfs(s-1);
  for(int i=0;i<n;i++)
    g<<visited[i]<<" ";
  return 0;
}