/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode() : val(0), left(nullptr), right(nullptr) {}
 *     TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
 *     TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
 * };
 */
class Solution {
public:

    int maxdepth(TreeNode* root){

        if(root==nullptr){
            return 0;
        }

        return max(1+maxdepth(root->left),1+maxdepth(root->right));


    }

    void dfs(TreeNode* root,vector<vector<string>>& ans,int i,int j,int depth){

        if(root==nullptr){
            return;
        }


        depth--;
        ans[i][j]=to_string(root->val);

        if(i+1<ans.size()){
            dfs(root->left,ans,i+1,j-depth-1,depth);
            dfs(root->right,ans,i+1,j+depth+1,depth);
        }

        return;

    }


    vector<vector<string>> printTree(TreeNode* root) {


        vector<vector<string>> ans;

        int depth=maxdepth(root);

        cout<<depth<<endl;


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

            vector<string> temp;
            for(int j=0;j<pow(2,depth)-1;j++){
                temp.push_back("");
            }
            ans.push_back(temp);
        }

        dfs(root,ans,0,depth+depth%2-1,depth-1);

        return ans;
    }
};