Cod sursa(job #2303102)

Utilizator vranceanu.andi2014Vranceanu Andi vranceanu.andi2014 Data 15 decembrie 2018 16:46:09
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.16 kb
#include <fstream>
#include <queue>
#include <utility>
#include <vector>
#define LGMAX 100005
#define pii pair<int,int>
#define mp make_pair
using namespace std;

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

vector<int> g[LGMAX];
queue<pii> c;
int n, m, start;
int uz[LGMAX], cost[LGMAX];

void citire();
void bfs(int start);

int main()
{
    citire();
    for (int i=1; i<=n; i++)
    {
        cost[i] = -1;
    }
    bfs(start);
    for (int i=1; i<=n; i++)
    {
        fout << cost[i] << " ";
    }
    fout << '\n';
    return 0;
}

void citire()
{
    int x, y;
    fin >> n >> m >> start;
    for (int i=1; i<=m; i++)
    {
        fin >> x >> y;
        g[x].push_back(y);
    }
}
void bfs(int start)
{
    c.push(mp(start, 0));
    uz[start] = 1;
    while (!c.empty())
    {
        pii act = c.front();
        c.pop();
        cost[act.first] = act.second;
        for (int i=0; i<g[act.first].size(); i++)
        {
            if (!uz[g[act.first][i]])
            {
                uz[g[act.first][i]] = 1;
                c.push(mp(g[act.first][i], act.second + 1));
            }
        }
    }
}