277 def BeginBuildNumber (fsm):  argument
278     fsm.memory.append (fsm.input_symbol)
280 def BuildNumber (fsm):  argument
281     s = fsm.memory.pop ()
282     s = s + fsm.input_symbol
283     fsm.memory.append (s)
285 def EndBuildNumber (fsm):  argument
286     s = fsm.memory.pop ()
287     fsm.memory.append (int(s))
289 def DoOperator (fsm):  argument
290     ar = fsm.memory.pop()
291     al = fsm.memory.pop()
292     if fsm.input_symbol == '+':
293         fsm.memory.append (al + ar)
294     elif fsm.input_symbol == '-':
295         fsm.memory.append (al - ar)
296     elif fsm.input_symbol == '*':
297         fsm.memory.append (al * ar)
298     elif fsm.input_symbol == '/':
299         fsm.memory.append (al / ar)
301 def DoEqual (fsm):  argument
302     print(str(fsm.memory.pop()))
304 def Error (fsm):  argument
306     print(str(fsm.input_symbol))