Cod sursa(job #2494321)

Utilizator natrovanCeval Marius natrovan Data 17 noiembrie 2019 18:01:47
Problema BFS - Parcurgere in latime Scor 80
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.04 kb
#include <iostream>
#include <fstream>
#include <list>
#include <iterator>
#include <queue>

using namespace std;
ifstream fin("bfs.in");
ofstream fout("bfs.out");

list<int>graph[200005];
queue<int>nodeToBeVisited;
int marked[200005];
int n, m, x, y, source;

void BFS(int currentNode){
    marked[currentNode] = 0;
    nodeToBeVisited.push(currentNode);

    while(!nodeToBeVisited.empty()){
        currentNode = nodeToBeVisited.front();

        for(list<int>::iterator it = graph[currentNode].begin(); it != graph[currentNode].end(); it++)
        if(marked[*it] == -1){
            marked[*it] = marked[currentNode] + 1;
            nodeToBeVisited.push(*it);
        }

        nodeToBeVisited.pop();
    }
}

int main()
{
    fin >> n >> m >> source;
    for(int i = 1; i <= m; i++){
        fin >> x >> y;
        graph[x].push_back(y);
    }

    for(int i = 1; i <= m; i++)
        marked[i] = -1;

    BFS(source);

    for(int i = 1; i <= n; i++)
        fout << marked[i] << ' ';


    return 0;
}