2019-09-05

Author: JiayangWu

.vscode/settings.json

@@ -0,0 +1,3 @@
+{
+    "python.pythonPath": "C:\\ProgramData\\Anaconda2\\envs\\py3\\python.exe"
+}

0280.摆动排序/0280-摆动排序.py

@@ -0,0 +1,17 @@
+class Solution(object):
+    def wiggleSort(self, nums):
+        """
+        :type nums: List[int]
+        :rtype: None Do not return anything, modify nums in-place instead.
+        """
+        if not nums:
+            return nums
+        i = 0
+        while i < len(nums):
+            if i % 2 == 0 and i < len(nums) - 1 and nums[i] > nums[i + 1]:
+                nums[i], nums[i + 1] = nums[i + 1], nums[i]
+            elif i % 2 and i < len(nums) - 1 and nums[i] < nums[i + 1]:
+                nums[i], nums[i + 1] = nums[i + 1], nums[i]
+            else:
+                i += 1
+        return nums

0281.锯齿迭代器/0281-锯齿迭代器.py

@@ -6,35 +6,36 @@ def __init__(self, v1, v2):
         :type v1: List[int]
         :type v2: List[int]
         """
-        self.list = []
-        if v1 and v2:
-            i = 0
-            for i in range(min(len(v1), len(v2))):
-                self.list.append(v1[i])
-                self.list.append(v2[i])
-            if v1[i + 1:]:
-                self.list += v1[i + 1:]
-            else:
-                self.list += v2[i + 1:]
-            
-        elif v1:
-            self.list = v1
-        else:
-            self.list = v2
-        self.index = 0
+        self.i1, self.i2 = 0, 0
+        self.v1, self.v2 = v1, v2
+        self.indicator = 0 # 0 for v1, 1 for v2
+
     def next(self):
         """
         :rtype: int
         """
-        self.index += 1
-        return self.list[self.index - 1]
+        if not self.indicator:
+            self.indicator = 1
+            if self.i1 < len(self.v1):
+                self.i1 += 1
+                return self.v1[self.i1 - 1]
+            else:
+                self.i2 += 1
+                return self.v2[self.i2 - 1]
+        else:
+            self.indicator = 0
+            if self.i2 < len(self.v2):
+                self.i2 += 1
+                return self.v2[self.i2 - 1]
+            else:
+                self.i1 += 1
+                return self.v1[self.i1 - 1]                  
 
     def hasNext(self):
         """
         :rtype: bool
         """
-        return self.index != len(self.list)
-        
+        return self.i1 < len(self.v1) or self.i2 < len(self.v2)
 
 # Your ZigzagIterator object will be instantiated and called as such:
 # i, v = ZigzagIterator(v1, v2), []

0283.移动零/0283-移动零.py

@@ -2,15 +2,12 @@ class Solution(object):
     def moveZeroes(self, nums):
         """
         :type nums: List[int]
-        :rtype: void Do not return anything, modify nums in-place instead.
+        :rtype: None Do not return anything, modify nums in-place instead.
         """
-        l = len(nums)
-        for index,item in enumerate(nums):
-            if item != 0:
-                continue
-            else:
-                for index0 in range(index+1,l):
-                    if nums[index0] != 0:
-                        print nums[index], nums[index0]
-                        nums[index], nums[index0] = nums[index0], nums[index]
-                        break
+        i = 0 
+        for j in range(len(nums)):
+            if nums[j] != 0:
+                nums[i], nums[j] = nums[j], nums[i]
+                i += 1
+                
+        # return nums

0284.顶端迭代器/0284-顶端迭代器.py

@@ -25,32 +25,32 @@ def __init__(self, iterator):
         Initialize your data structure here.
         :type iterator: Iterator
         """
-        self.list = list()
-        while(iterator.hasNext()):
-            self.list.append(iterator.next())
+        self.l = []
+        while iterator.hasNext():
+            self.l.append(iterator.next())
+        # self.l = iterator
+        self.index = 0
+        
 
     def peek(self):
         """
         Returns the next element in the iteration without advancing the iterator.
         :rtype: int
         """
-        return self.list[0]
-        
+        return self.l[self.index]
 
     def next(self):
         """
         :rtype: int
         """
-        return self.list.pop(0)
-        
-        
+        self.index += 1
+        return self.l[self.index - 1]
 
     def hasNext(self):
         """
         :rtype: bool
         """
-        return len(self.list) != 0
-        
+        return self.index < len(self.l)
 
 # Your PeekingIterator object will be instantiated and called as such:
 # iter = PeekingIterator(Iterator(nums))

0285.二叉搜索树中的顺序后继/0285-二叉搜索树中的顺序后继.py

@@ -0,0 +1,23 @@
+# Definition for a binary tree node.
+# class TreeNode(object):
+#     def __init__(self, x):
+#         self.val = x
+#         self.left = None
+#         self.right = None
+
+class Solution(object):
+    def inorderSuccessor(self, root, p):
+        """
+        :type root: TreeNode
+        :type p: TreeNode
+        :rtype: TreeNode
+        """
+        if not root:
+            return None
+        def inorder(node):
+            if not node:
+                return []
+            return inorder(node.left) + [node] + inorder(node.right)
+        l = inorder(root)
+        i = l.index(p)
+        return l[i + 1] if i < len(l) - 1 else None