2020-01-23

0905.按奇偶排序数组/0905-按奇偶排序数组.py

@@ -4,11 +4,4 @@ def sortArrayByParity(self, A):
         :type A: List[int]
         :rtype: List[int]
         """
-        odd, even = [], []
-        for i in A:
-            if i % 2:
-                odd.append(i)
-            else:
-                even.append(i)
-
-        return even + odd
+        return sorted(A, key = lambda x:x % 2)

0921.使括号有效的最少添加/0921-使括号有效的最少添加.py

@@ -1,19 +1,14 @@
-# -*- coding: utf-8 -*-
 class Solution(object):
     def minAddToMakeValid(self, S):
         """
         :type S: str
         :rtype: int
         """
-        dic = {"(":"", ")" : "("}
-        res = len(S)
-        temp = [None]
-        for item in S:
-            # print item
-            if temp[-1] != dic[item.encode('utf-8')]:
-                temp.append(item)
+        stack = []
+        dic = {"(":")", "{":"}", "[":"]"}
+        for ch in S:
+            if stack and stack[-1] in dic and dic[stack[-1]] == ch:
+                stack.pop()
             else:
-                temp = temp[:-1]
-        return len(temp) -1
-
-
+                stack.append(ch)
+        return len(stack)