cleanup 772 syntax

Author: fxrcode

solution/0700-0799/0772.Basic Calculator III/README.md

@@ -76,30 +76,27 @@ tags:
 class Solution:
     def calculate(self, s: str) -> int:
         def dfs(q):
-            num, sign = 0, "+"
-            stk = []
+            num, sign, stk = 0, "+", []
             while q:
                 c = q.popleft()
                 if c.isdigit():
-                    num = num * 10 + int(c)
-                if c == "(":
+                    num = num*10 + int(c)
+                if c == '(':
                     num = dfs(q)
-                if c in "+-*/)" or not q:
-                    #! careful we catch ')' to eval (...), ow  (4-5/2) will only be sum([4,-5]) => -1, /2 is ignored
-                    if sign == "+":
-                        stk.append(num)
-                    elif sign == "-":
-                        stk.append(-num)
-                    elif sign == "*":
-                        stk.append(stk.pop() * num)
-                    elif sign == "/":
-                        stk.append(int(stk.pop() / num))
-                    sign = c
-                    num = 0
+                if c in '+-*/)' or not q:
+                    match sign:
+                        case "+":
+                            stk.append(num)
+                        case "-":
+                            stk.append(-num)
+                        case "*":
+                            stk.append(stk.pop()*num)
+                        case "/":
+                            stk.append(int(stk.pop()/num))
+                    num, sign = 0, c
                 if c == ")":
                     break
             return sum(stk)
-
         return dfs(deque(s))
 ```