struct ListNode {

public:

    int val;   // 节点值

    ListNode* next;    // 下一个节点

    ListNode(int n) :val(n), next(nullptr) {}  // 构造函数

    ListNode(int n, ListNode* next) :val(n), next(next) {} 

};

ListNode* getListNodemy(vector<int> &str) {

    ListNode* dumyHead = new ListNode(-1);

    ListNode* ptr = dumyHead;

    int nums = str.size();

    int i = 0;

    while (i<nums) {

        dumyHead->next =new ListNode(str[i]);

        dumyHead = dumyHead->next;

        i++;

    }

    return ptr->next;

}

struct TreeNode {

    int val;

    TreeNode *left;

    TreeNode *right;

    TreeNode(int x) : val(x), left(NULL), right(NULL) {}

};

// 根据数组构造二叉树

TreeNode* construct_binary_tree(const vector<int>& vec) {

    vector<TreeNode*> vecTree (vec.size(), NULL);

    TreeNode* root = NULL;

    for (int i = 0; i < vec.size(); i++) {

        TreeNode* node = NULL;

        if (vec[i] != -1) node = new TreeNode(vec[i]);

        vecTree[i] = node;

        if (i == 0) root = node;

    }

    for (int i = 0; i * 2 + 1 < vec.size(); i++) {

        if (vecTree[i] != NULL) {

            vecTree[i]->left = vecTree[i * 2 + 1];

            if(i * 2 + 2 < vec.size())

            vecTree[i]->right = vecTree[i * 2 + 2];

        }

    }

    return root;

}

// 层序打印二叉树

void print_binary_tree(TreeNode* root) {

    queue<TreeNode*> que;

    if (root != NULL) que.push(root);

    vector<vector<int>> result;

    while (!que.empty()) {

        int size = que.size();

        vector<int> vec;

        for (int i = 0; i < size; i++) {

            TreeNode* node = que.front();

            que.pop();

            if (node != NULL) {

                vec.push_back(node->val);

                que.push(node->left);

                que.push(node->right);

            }

            // 这里的处理逻辑是为了把 null 节点打印出来，用 - 1 表示 null

            else vec.push_back(-1);

        }

        result.push_back(vec);

    }

    for (int i = 0; i < result.size(); i++) {

        for (int j = 0; j < result[i].size(); j++) {

            cout << result[i][j] << " ";

        }

        cout << endl;

    }

}

while(cin>>n){

}