





from __future__ import annotations

from typing import Any


def     SCREAMING_SNAKE_CASE			(      lowerCAmelCase					):
       if not postfix_notation:
              return 0

       _UpperCamelCase              =						{'''+''', '''-''', '''*''', '''/'''}
       _UpperCamelCase              =						[]

       for token in postfix_notation:
              if token in operations:
                     _UpperCamelCase       ,		_UpperCamelCase              =						stack.pop(), stack.pop()
                     if token == "+":
                            stack.append(a + b					)
                     elif token == "-":
                            stack.append(a - b					)
                     elif token == "*":
                            stack.append(a * b					)
                     else:
                            if a * b < 0 and a % b != 0:
                                   stack.append(a // b + 1					)
                            else:
                                   stack.append(a // b					)
              else:
                     stack.append(int(lowerCAmelCase					)					)

       return stack.pop()


if __name__ == "__main__":
       import doctest

       doctest.testmod()













from __future__ import annotations

from collections.abc import Iterator

class  __A:

     def __init__(      self,       A      ):





            """simple docstring"""

            _UpperCamelCase              =						value
            _UpperCamelCase              =						None
            _UpperCamelCase              =						None






class  __A:

     def __init__(      self,       A      ):





            """simple docstring"""

            _UpperCamelCase              =						tree

     def 	_UpperCamelCase     (      self,       A      ):





            """simple docstring"""

            if node is None:
                   return 0
            return node.value + (
                self.depth_first_search(node.left      ) + self.depth_first_search(node.right      )
            )



     def __iter__(      self      ):





            """simple docstring"""

            yield self.depth_first_search(self.tree      )


if __name__ == "__main__":
       import doctest

       doctest.testmod()






