#!/usr/bin/env python3
import sys
import math

def calc(o1, oper, o2):
   if oper == '+': return o1 + o2
   if oper == '-': return o1 - o2
   if oper == '*': return o1 * o2
   if oper == '/': return o1 // o2
   if oper == '^': return int(math.pow(o1, o2))


def compare_priority(oper1, oper2):
   priority = {'+':0, '-':0, '/':1, '*':1, '^':2}
   return priority[oper1] - priority[oper2]


def is_oper(e):
   return e in list("+-/*^")


def is_paren(e):
   return e in ['(', ')']


def is_unary(e):
   return e in ['-', '+']

def calc_at_idx(parsed_exp, idx):
      new_val = calc(parsed_exp[idx - 3], parsed_exp[idx - 2], parsed_exp[idx - 1])
      del parsed_exp[idx - 3]
      del parsed_exp[idx - 3]
      #print("got", new_val)
      parsed_exp[idx - 3] = new_val

expression = sys.argv[1].replace(' ', '')
parsed_exp = []

acc = ''
for c in expression:
   if c in '+-*/^()':
       if acc:
          parsed_exp.append(int(acc))
          acc = ''
       parsed_exp.append(c)
   else:
       acc += c
if acc: parsed_exp.append(int(acc))

idx = 0
openp_idx = -1
while len(parsed_exp) > 1:
   #print(parsed_exp)
   #print(idx)
   if parsed_exp[idx] == '(':
      openp_idx = idx
   elif parsed_exp[idx] == ')' and idx - openp_idx >= 4:
      # (14 - 5) -> (9)
      calc_at_idx(parsed_exp, idx)
      idx = -1
   elif parsed_exp[idx] == ')' and idx - openp_idx == 2:
      # (5) -> 5
      del parsed_exp[idx]
      del parsed_exp[idx-2]
      idx = -1
   elif (idx == 0 or parsed_exp[idx-1] == '(') and is_unary(parsed_exp[idx]):
      # unary + or -
      # +5 -> 5
      # -(5+2) -> -1 * (5+2)
      if parsed_exp[idx] == '+':
         del parsed_exp[idx]
         idx -= 1
      else:
         parsed_exp[idx] = '*'
         parsed_exp.insert(idx, -1)
         idx = -1
   elif is_oper(parsed_exp[idx]) and is_oper(parsed_exp[idx-2]):
      # 4*5+1 (calc on a lower priority operand)
      if compare_priority(parsed_exp[idx], parsed_exp[idx-2]) <= 0:
         calc_at_idx(parsed_exp, idx)
         idx = -1
      else:
         pass
   elif idx == len(parsed_exp) - 1 and is_oper(parsed_exp[idx-1]):
      # 5-4 (calc on end of expr)
      calc_at_idx(parsed_exp, idx+1)
      idx = -1
   idx += 1

result = parsed_exp[0]
print(expression, '=', result)
if len(sys.argv) == 3:
   if result == int(sys.argv[2]):
      print("PASS")
   else:
      print("FAIL")