#include <iostream>
#include <queue>
using namespace std;

struct edge
{
    int idx;
    int a;
    int b;
    int cost;
};

struct vertex
{
    bool visited = false;
    std::vector<struct edge> adj_list;
    int count_edges = 0;
};

void addEdge(int i, int j, int cost, vector<vertex>& vertexes)
{
    edge buff;

    buff.idx = j;
    buff.edge_value = cost;

    vertexes[i].adj_list.push_back(buff);

    buff.idx = i;
    vertexes[j].adj_list.push_back(buff);

    vertexes[i].count_edges++;
    vertexes[j].count_edges++;
}


struct Compare
{
    bool operator()(edge& o1, edge& o2) const
    {
        return o1.cost > o2.cost;
    }
};

void showpq(priority_queue<struct edge, vector<struct edge>, Compare> gq)
{
    priority_queue<struct edge, vector<struct edge>, Compare> g = gq;
    while (!g.empty())
    {
        cout << '\t' << g.top().cost;
        g.pop();
    }
    cout << '\n';
}

int main()
{
    priority_queue<struct edge, vector<struct edge>, Compare> heap;

    int n, m;
    cin >> n >> m;

    int a,b,c;
    vector<struct vertex> vertexes(n);
    struct edge edge;

    for (int i = 0; i < m; ++i)
    {
        cin >> a >> b >> c;

        addEdge(a-1, b-1, cost, vertexes);

        if (a == 1 | b == 1)
        {
            edge.a = a;
            edge.b = b;
            edge.cost = cost;
            heap.push(edge);
        }
    }

    visited[0] = true;
    struct edge edge;
    int new;
    int max = 0;

    for (int i = 0; i < n; ++i)
    {
        edge = heap.pop();

        if (max < edge.cost)
            max = edge.cost;

        if (visited[edge.a - 1])
        {
            new = edge.b - 1;
            visited[new] = true;
        }
        else
        {
            new = edge.a - 1;
            visited[new] = true;
        }

        for (int j = 0; j < vertexes[new].count_edges; ++j)

            edge edge = vertexes[new].adj_list[j];

        if (not vertexes[edge.idx].visited)
            heap.push(edge);
    }


    return 0;
}