void read_game_tree(binary_tree_node<string>* tree, ifstream &fin) {
    string s, dat;
    char space;
    fin >> s;
    fin >> space;
    getline(fin, dat);
    tree->data = dat;
    if (s == "#A") {
        return;
    }
    else {
        read_game_tree(tree->left, fin);
        read_game_tree(tree->right, fin);
    }
}