#include <iostream>
#include <assert.h>
#include <vector>
#include <utility>
#include <queue>
#include <unordered_map>

struct IGraph {
    virtual ~IGraph() {}

    // Добавление ребра от from к to.
    virtual void AddEdge(int from, int to, int value) = 0;

    virtual int VerticesCount() const = 0;

    virtual void GetNextVertices(int vertex, std::vector<std::pair<int, int>> &vertices) const = 0;
    virtual void GetPrevVertices(int vertex, std::vector<std::pair<int, int>> &vertices) const = 0;
};

struct ListGraph : public IGraph {
    explicit ListGraph(int count);
    ListGraph(const IGraph& graph);
    virtual ~ListGraph() = default;

    // Добавление ребра от from к to.
    virtual void AddEdge(int from, int to, int value);

    virtual int VerticesCount() const;
    virtual void GetNextVertices(int vertex, std::vector<std::pair<int, int>>& vertices) const;
    virtual void GetPrevVertices(int vertex, std::vector<std::pair<int, int>>& vertices) const;

private:
    std::vector<std::vector<std::pair<int, int>>> Matrix;
};

ListGraph::ListGraph(int count) {
    Matrix.resize(count);
};

ListGraph::ListGraph(const IGraph& graph) {
    Matrix.resize(graph.VerticesCount());
    for (int i = 0; i < Matrix.size(); i++) {
        graph.GetNextVertices(i, Matrix[i]);
    }
};

void ListGraph::AddEdge(int from, int to, int value) {
    assert(from >= 0 && from < Matrix.size());
    assert(to >= 0 && to < Matrix.size());
    Matrix[from].push_back({ to, value });
};

int ListGraph::VerticesCount() const {
    return Matrix.size();
};

void ListGraph::GetNextVertices(int vertex, std::vector<std::pair<int, int>>& vertices) const {
    assert(vertex >= 0 && vertex < Matrix.size());
    vertices = Matrix[vertex];
};

void ListGraph::GetPrevVertices(int vertex, std::vector<std::pair<int, int>>& vertices) const {
    assert(vertex >= 0 && vertex < Matrix.size());
    vertices.clear();
    for (int i = 0; i < Matrix.size(); i++) {
        for (int j = 0; j < Matrix[i].size(); j++) {
            if (Matrix[i][j].first == vertex) {
                vertices.push_back({ i, Matrix[i][j].second });
                break;
            }
        }
    }
};

bool compare(const std::pair<int, int> &a, const std::pair<int, int> &b) {
    return a.second < b.second;
}

int min_tree(IGraph &input) {
    std::vector<int> weight = std::vector<int>(input.VerticesCount(), INT_MAX);
    int ans = 0;
    weight[0] = 0;
    std::priority_queue<std::pair<int, int>, std::vector<std::pair<int, int>>, decltype(&compare)> list(&compare);
    list.push({ 0, 0 });
    while (!list.empty()) {
        std::pair<int, int> v = list.top();
        list.pop();
        std::vector<std::pair<int, int>> transfer;
        input.GetNextVertices(v.first, transfer);
        for (std::pair<int, int> u : transfer){
            if (weight[u.first] != INT_MAX)
                ans -= weight[u.first];
            if (weight[u.first] > u.second) {
                int w = u.second;
                weight[u.first] = w;
                list.push({ u.first, w });
            }
            ans += weight[u.first];
        }
    }
    return ans;
}

int main() {
    int n;
    std::cin >> n;
    ListGraph input(n);
    std::cin >> n;
    int from, to, value;
    for (int i = 0; i < n; i++) {
        std::cin >> from >> to >> value;
        from -= 1;
        to -= 1;
        input.AddEdge(from, to, value);
        input.AddEdge(to, from, value);
    }

    std::cout << min_tree(input);
    return 0;
}