Binary Tree - medium - longest consecutive sequence implementation

Author: rajithst

binary_tree/medium/longest_consecutive_sequence.py

@@ -0,0 +1,33 @@
+# Definition for a binary tree node.
+from typing import Optional
+
+
+class TreeNode:
+    def __init__(self, val=0, left=None, right=None):
+        self.val = val
+        self.left = left
+        self.right = right
+
+
+class TreeInfo:
+    def __init__(self, val):
+        self.max_length = val
+
+
+class Solution:
+    def longestConsecutive(self, root: Optional[TreeNode]) -> int:
+
+        def dfs(node, parent, current_length, treeInfo):
+            if not node:
+                return
+            if parent is not None and parent.val + 1 == node.val:
+                current_length += 1
+            else:
+                current_length = 1
+            treeInfo.max_length = max(treeInfo.max_length, current_length)
+            dfs(node.left, node, current_length, treeInfo)
+            dfs(node.right, node, current_length, treeInfo)
+
+        ti = TreeInfo(0)
+        dfs(root, None, 0, ti)
+        return ti.max_length