text: /*
   * @lc app=leetcode.cn id=958 lang=javascript
   *
   * [958] 二叉树的完全性检验
   */
  
  // @lc code=start
  /**
   * Definition for a binary tree node.
   * function TreeNode(val) {
   *     this.val = val;
   *     this.left = this.right = null;
   * }
   */
  /**
   * @param {TreeNode} root
   * @return {boolean}
   */
  var isCompleteTree = function(root) {
  
  };
  // @lc code=end
  
  //* Testcase Example: '[1,2,3,4,5,6]'