Merge pull request neetcode-gh#2904 from sahasourav17/main

sujal-goswami · web-flow · commit db4d80f82753 · 2023-08-25T13:24:32.000+05:30
Create: 0103-binary-tree-zigzag-level-order-traversal.py
diff --git a/python/0103-binary-tree-zigzag-level-order-traversal.py b/python/0103-binary-tree-zigzag-level-order-traversal.py
@@ -0,0 +1,24 @@
+# Definition for a binary tree node.
+# class TreeNode:
+#     def __init__(self, val=0, left=None, right=None):
+#         self.val = val
+#         self.left = left
+#         self.right = right
+class Solution:
+    def zigzagLevelOrder(self, root: Optional[TreeNode]) -> List[List[int]]:
+        if root is None:
+            return
+        result, zigzagDirection = [], 1
+        q = [root]
+        while q:
+            level, queueLength = [], len(q)
+            for i in range(queueLength):
+                node = q.pop(0)
+                level.append(node.val)
+                if node.left:
+                    q.append(node.left)
+                if node.right:
+                    q.append(node.right)
+            result.append(level[::zigzagDirection])
+            zigzagDirection *= -1
+        return result
diff --git a/python/0108-convert-sorted-array-to-binary-search-tree.py b/python/0108-convert-sorted-array-to-binary-search-tree.py
@@ -0,0 +1,15 @@
+# Definition for a binary tree node.
+# class TreeNode:
+#     def __init__(self, val=0, left=None, right=None):
+#         self.val = val
+#         self.left = left
+#         self.right = right
+class Solution:
+    def sortedArrayToBST(self, nums: List[int]) -> Optional[TreeNode]:
+        if not nums:
+            return None
+        mid = len(nums)//2
+        root = TreeNode(nums[mid])
+        root.left = self.sortedArrayToBST(nums[:mid])
+        root.right = self.sortedArrayToBST(nums[mid+1:])
+        return root
