struct Node{

    string name;
    bool mark;
};

struct graph{

    long long int first(Node*);
    long long int next(Node*, long long int);
    pair<long long int, Node*> vertex(Node*, long long int);
    void edit_v(Node*, long long int);
    vector<Node*> nodes;
};

void dfs(Node*& node, graph& g, vector<string>& res, long long int k, string way = "") {
    if (node->mark || k < 0)
        return;
    way += ' ' + node->name;
    if (k == 0) {
        res.push_back(way);
        return;
    }
    g.edit_v(node, true);
    for (long long index = g.first(node); index != -1; index = g.next(node, index)) {
        auto v = g.vertex(node, index);
        dfs(v.second, g, res, k - v.first, way);
    }
    g.edit_v(node, false);
}

vector<string> get_ways(graph& g, long long int k) {
    vector<string> res;
    for (auto& x : g.nodes) {
        dfs(x, g, res, k, "");
    }
    return res;
}