Cod sursa(job #2569987)

Utilizator FrostfireMagirescu Tudor Frostfire Data 4 martie 2020 14:34:09
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.95 kb
#include <iostream>
#include <fstream>
#include <queue>
#define NMAX 100000

using namespace std;

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

int n, m, s, viz[NMAX+10], dist[NMAX+10];
vector <int> nod[NMAX+10];
queue <int> Q;

void bfs(int x)
{   viz[x] = 1;
    Q.push(x);
    while(!Q.empty())
        {   int a = Q.front();
            Q.pop();
            for(int i=0; i<nod[a].size(); i++)
                if(!viz[nod[a][i]])
                    {   viz[nod[a][i]] = 1;
                        dist[nod[a][i]] = dist[a] + 1;
                        Q.push(nod[a][i]);
                    }
        }
}

int main()
{
    f >> n >> m >> s;
    for(int i=1; i<=m; i++)
        {   int nod1, nod2;
            f >> nod1 >> nod2;
            nod[nod1].push_back(nod2);
        }
    for(int i=1; i<=n; i++) dist[i] = -1;
    dist[s] = 0;
    bfs(s);
    for(int i=1; i<=n; i++) g << dist[i] << ' ';
    g << '\n';
    return 0;
}