text: /*
   * @lc app=leetcode.cn id=508 lang=javascript
   *
   * [508] 出现次数最多的子树元素和
   */
  
  // @lc code=start
  /**
   * Definition for a binary tree node.
   * function TreeNode(val) {
   *     this.val = val;
   *     this.left = this.right = null;
   * }
   */
  /**
   * @param {TreeNode} root
   * @return {number[]}
   */
  var findFrequentTreeSum = function(root) {
  
  };
  // @lc code=end
  
  //* Testcase Example: '[5,2,-3]'