Cod sursa(job #1795034)

Utilizator valentinoMoldovan Rares valentino Data 1 noiembrie 2016 21:59:39
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.03 kb
#include <stdio.h>
#include <queue>
#include <fstream>
#include <algorithm>
#include <iostream>
#include <vector>
#define INF 0x3f3f3f3f
#define NM 100005
using namespace std;

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

vector < int > a[NM];
queue < int > coada;
int l[NM], cost[NM];
int n, m, st;

void BFS(int nod)
{
    int nod2, minn;
    for(int i = 1; i <= NM - 1; ++i)
        cost[i] = -1;
    cost[nod] = 0;
    coada.push(nod);
    while(!coada.empty())
    {
        nod2 = coada.front();
        coada.pop();
        for(int i = 0; i < l[nod2]; ++i)
        {
            if(cost[ a[nod2][i] ] == -1)
                cost[a[nod2][i]] = cost[nod2] + 1, coada.push(a[nod2][i]);
        }


    }
}

int main()
{
    int x, y;
    f >> n >> m >> st;
    for(int i = 1; i <= m; ++i)
    {
        f >> x >> y;
        a[x].push_back(y);
        l[x]++;//liste de adiacenta..l[i] - dimensiunea vectorului a[i]
    }
    BFS(st);
    for(int i = 1; i <= n; ++i)
        g << cost[i]  << ' ';

}