algorithm019 · PeterPaaan · Nov 8, 2020 · Nov 8, 2020 · Nov 8, 2020
diff --git a/Week_01/20.有效的括号.py b/Week_01/20.有效的括号.py
@@ -0,0 +1,21 @@
+#
+# @lc app=leetcode.cn id=20 lang=python3
+#
+# [20] 有效的括号
+#
+
+# @lc code=start
+class Solution:
+    def isValid(self, s: str) -> bool:
+        if len(s) % 2: return False 
+        smap = {'(':')', '{': '}', '[': ']', '?': '?'}
+        stack = ['?']
+        for c in s:
+            if c in smap:
+                stack.append(c)
+            elif smap[stack.pop()] != c:
+                return False 
+        return stack == ['?']
+
+# @lc code=end
+
diff --git a/Week_01/88.合并两个有序数组.py b/Week_01/88.合并两个有序数组.py
@@ -0,0 +1,24 @@
+#
+# @lc app=leetcode.cn id=88 lang=python3
+#
+# [88] 合并两个有序数组
+#
+
+# @lc code=start
+class Solution:
+    def merge(self, nums1: List[int], m: int, nums2: List[int], n: int) -> None:
+        """
+        Do not return anything, modify nums1 in-place instead.
+        """
+        p, p1, p2 = m + n - 1, m - 1, n - 1 
+        while p1 >= 0 and p2 >= 0:
+            if nums1[p1] > nums2[p2]:
+                nums1[p] = nums1[p1]
+                p1 -= 1 
+            else:
+                nums1[p] = nums2[p2]
+                p2 -= 1
+            p -= 1
+        nums1[:p2 + 1] = nums2[:p2 + 1]
+# @lc code=end
+