Create even-odd-tree.py

Author: kamyu104

Python/even-odd-tree.py

@@ -0,0 +1,37 @@
+# Time:  O(n)
+# Space: O(w)
+
+# Definition for a binary tree node.
+class TreeNode(object):
+    def __init__(self, val=0, left=None, right=None):
+        self.val = val
+        self.left = left
+        self.right = right
+
+
+class Solution(object):
+    def isEvenOddTree(self, root):
+        """
+        :type root: TreeNode
+        :rtype: bool
+        """
+        q = [root]
+        is_odd = False
+        while q:
+            new_q = []
+            prev = None
+            for node in q:
+                if is_odd:
+                    if node.val%2 or (prev and prev.val <= node.val):
+                        return False
+                else:
+                    if not node.val%2 or (prev and prev.val >= node.val):
+                        return False
+                if node.left:
+                    new_q.append(node.left)
+                if node.right:
+                    new_q.append(node.right)
+                prev = node
+            q = new_q
+            is_odd = not is_odd
+        return True