import pyutil as pyu
pyu.get_local_pyinfo()

print(pyu.ps2("python-dotenv"))

from typing import List

class Solution:
  def findDuplicateSubtrees(self, root: Optional[TreeNode]) -> List[Optional[TreeNode]]:
    ans = []
    count = Counter()

    def encode(root: Optional[TreeNode]) -> str:
      if not root:
        return ''

      encoded = str(root.val) + '#' + \
          encode(root.left) + '#' + \
          encode(root.right)
      count[encoded] += 1
      if count[encoded] == 2:
        ans.append(root)
      return encoded

    encode(root)
    return ans

new Solution().findDuplicateSubtrees()