Cod sursa(job #1754262)

Utilizator meriniucrMeriniuc Razvan- Dumitru meriniucr Data 7 septembrie 2016 19:39:26
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.98 kb
#include <fstream>
#include <vector>
#include <queue>
#include <string.h>

std::vector <int> v[100001];
int cost[100001];
bool vis[1000001];
int n;

void
go(int s)
{
    std::queue <int> q;
    int node;

    memset(cost, -1, (n + 1) << 2);
    q.push(s);
    cost[s] = 0;
    vis[s] = true;
    while (not q.empty())
    {
        node = q.front();
        q.pop();

        for (int i = 0; i < (int)v[node].size(); ++i)
        {
            if (not vis[v[node][i]])
            {
                cost[v[node][i]] = cost[node] + 1;
                vis[v[node][i]] = true;
                q.push(v[node][i]);
            }
        }
    }
}

int main()
{
    int m;
    int s;
    int x;
    int y;

    std::ifstream mama("bfs.in");
    std::ofstream tata("bfs.out");

    mama >> n >> m >> s;

    for (int i = 0; i < m; ++i)
    {
        mama >> x >> y;

        v[x].push_back(y);
    }

    go(s);

    for (int i = 1; i <= n; ++i)
    {
        tata << cost[i] << ' ';
    }

    return 0;
}