


__UpperCAmelCase       :       Union[str, Any]       	= {
    '''+''': lambda x, y: x + y,
    '''-''': lambda x, y: x - y,
    '''*''': lambda x, y: x * y,
    '''/''': lambda x, y: x / y,
}


def    a		(							SCREAMING_SNAKE_CASE_					:						Union[str, Any]				):






       """simple docstring"""





       return c.isdigit()


def    a		(							SCREAMING_SNAKE_CASE_					:						Any				):






       """simple docstring"""





       UpperCamelCase			:		Tuple      		=						[]

       # iterate over the string in reverse order
       for c in expression.split()[::-1]:
              # push operand to stack
              if is_operand(_UpperCAmelCase				):
                     stack.append(int(_UpperCAmelCase				)				)

              else:
                     # pop values from stack can calculate the result
                     # push the result onto the stack again
                     UpperCamelCase			:		Union[str, Any]      		=						stack.pop()
                     UpperCamelCase			:		str      		=						stack.pop()
                     stack.append(calc[c](_UpperCAmelCase							,	_UpperCAmelCase				)				)

       return stack.pop()


# Driver code
if __name__ == "__main__":
  __UpperCAmelCase       :       Tuple       	= '''+ 9 * 2 6'''
  print(evaluate(test_expression))

  __UpperCAmelCase       :       List[Any]       	= '''/ * 10 2 + 4 1 '''
  print(evaluate(test_expression))








"""simple docstring"""
import os
import sys
import time

from . import transposition_cipher as trans_cipher

def 						_SCREAMING_SNAKE_CASE       ():
 lowerCAmelCase  							=      'Prehistoric Men.txt'
 lowerCAmelCase  							=      'Output.txt'
 lowerCAmelCase  							=      int(input('Enter key: '       )       )
 lowerCAmelCase  							=      input('Encrypt/Decrypt [e/d]: '       )

 if not os.path.exists(_UpperCAmelCase       ):
  print(F'File {input_file} does not exist. Quitting...'       )
  sys.exit()
 if os.path.exists(_UpperCAmelCase       ):
  print(F'Overwrite {output_file}? [y/n]'       )
  lowerCAmelCase  							=      input('> '       )
  if not response.lower().startswith('y'       ):
   sys.exit()

 lowerCAmelCase  							=      time.time()
 if mode.lower().startswith('e'       ):
  with open(_UpperCAmelCase       ) as f:
   lowerCAmelCase  							=      f.read()
  lowerCAmelCase  							=      trans_cipher.encrypt_message(_UpperCAmelCase   ,			_UpperCAmelCase       )
 elif mode.lower().startswith('d'       ):
  with open(_UpperCAmelCase       ) as f:
   lowerCAmelCase  							=      f.read()
  lowerCAmelCase  							=      trans_cipher.decrypt_message(_UpperCAmelCase   ,			_UpperCAmelCase       )

 with open(_UpperCAmelCase   ,			'w'       ) as output_obj:
  output_obj.write(_UpperCAmelCase       )

 lowerCAmelCase  							=      round(time.time() - start_time   ,			2       )
 print(('Done (', total_time, 'seconds )')       )


if __name__ == "__main__":
       main()





