Given the `root`

of a binary tree, return the most frequent **subtree sum**. If there is a tie, return all the values with the highest frequency in any order.

The **subtree sum** of a node is defined as the sum of all the node values formed by the subtree rooted at that node (including the node itself).

**Example 1:**

Input:root = [5,2,-3]Output:[2,-3,4]

**Example 2:**

Input:root = [5,2,-5]Output:[2]

**Constraints:**

- The number of nodes in the tree is in the range
`[1, 10`

.^{4}] `-10`

^{5}<= Node.val <= 10^{5}