added daily challenge

Author: Pasindu-Vishmika

1609. Even Odd Tree.py

@@ -0,0 +1,33 @@
+# 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 isEvenOddTree(self, root: Optional[TreeNode]) -> bool:
+        if not root:
+            return True
+
+        queue = deque([root])
+        level = 0
+
+        while queue:
+            prev_val = None 
+
+            for _ in range(len(queue)):
+                node = queue.popleft()
+                if (level % 2 == 0 and (node.val % 2 == 0 or (prev_val is not None and node.val <= prev_val))) or \
+                   (level % 2 == 1 and (node.val % 2 == 1 or (prev_val is not None and node.val >= prev_val))):
+                    return False
+
+                prev_val = node.val
+                if node.left:
+                    queue.append(node.left)
+                if node.right:
+                    queue.append(node.right)
+
+            level += 1
+        return True   
+