These problems are related to tree.
Lowest common ancestor of a binary tree IV - August 7, 2023
Univalued binary tree - May 27, 2023
Kth largest sum in a binary tree - May 21, 2023
Number of good leaf nodes pairs - May 17, 2023
Diameter of N-ary tree - May 17, 2023
Equal tree partition - May 10, 2023
Increasing order search tree - May 9, 2023
Number of good paths - January 15, 2023
Longest path with different adjacent characters - January 13, 2023
Number of nodes in the sub tree with the same label - January 12, 2023
Minimum time to collect all apples in a tree - January 11, 2023
Two sum bsts - January 1, 2023
Create binary tree from descriptions - December 31, 2022
Convert binary search tree to sorted doubly linked list - December 23, 2022
Flatten a multilevel doubly linked list - December 23, 2022
Sum of distances in tree - December 22, 2022
Find distance in a binary tree - December 21, 2022
Binary tree longest consecutive sequence - December 19, 2022
Clone binary tree with random pointer - December 19, 2022
Root equals sum of children - December 17, 2022
Maximum level sum of a binary tree - December 12, 2022
Smallest subtree with all the deepest nodes - December 12, 2022
Lowest common ancestor of deepest leaves - December 12, 2022
Longest univalue path - December 12, 2022
Maximum product of splitted binary tree - December 10, 2022
Find root of N-ary tree - December 8, 2022
Range sum of bst - December 7, 2022
largest-bst-subtree - December 6, 2022
Path sum IV - December 1, 2022
Find leaves of binary tree - November 30, 2022
Maximum average subtree - November 30, 2022
Recover a tree from preorder traversal - November 30, 2022
Verify preorder sequence in binary search tree - November 30, 2022
Count nodes equal to average of subtree - November 30, 2022
Inorder successor in BST - November 29, 2022
Count univalue subtrees - November 29, 2022
Validate binary tree nodes - November 28, 2022
Binary tree vertical order traversal - November 28, 2022
Count nodes equal to sum of descendants - November 28, 2022
Binary tree upside down - November 27, 2022
Linked list in binary tree - November 21, 2022
All nodes distance k in binary tree - November 20, 2022
Symmetric tree - November 17, 2022
Construct binary search tree from preorder traversal - November 16, 2022
Delete nodes and return forest - November 16, 2022
Path in zigzag labelled binary tree - November 16, 2022
Trim a binary search tree - November 16, 2022
Insert into a binary search tree - November 16, 2022
Find mode in binary search tree - November 15, 2022
Most frequent subtree sum - November 15, 2022
Find duplicate subtrees - November 15, 2022
Maximum width of binary tree - November 15, 2022
Binary tree tilt - November 15, 2022
Path sum III - November 15, 2022
Leaf similar trees - November 12, 2022
Check completeness of a binary tree - November 6, 2022
Minimum absolute difference in bst - November 1, 2022
Search in a binary search tree - October 29, 2022
All elements in two binary search trees - October 28, 2022
Serialize and deserialize bst - October 25, 2022
Reverse odd levels of binary tree - October 25, 2022
Delete leaves with a given value - October 16, 2022
Convert bst to greater tree - October 9, 2022
Find bottom left tree value - October 9, 2022
Two sum IV input is a bst - October 9, 2022
Flip equivalent binary trees - October 9, 2022
Merge two binary trees - October 6, 2022
Add one row to tree - October 5, 2022
Deepest leaves sum - September 17, 2022
Insufficient nodes in root to leaf paths - September 14, 2022
Pseudo palindromic paths in a binary tree - September 14, 2022
Maximum difference between node and ancestor - September 11, 2022
Maximum binary tree II - September 10, 2022
Maximum binary tree - September 10, 2022
Print binary tree - September 7, 2022
Construct string from binary tree - September 7, 2022
Binary tree pruning - September 6, 2022
Binary tree zigzag level order traversal - September 4, 2022
Binary tree level order traversal II - September 4, 2022
Count complete tree nodes - September 4, 2022
Populating next right pointers in each node - September 4, 2022
Binary search tree iterator - September 4, 2022
Amount of time for binary tree to be infected - September 4, 2022
Convert sorted list to binary search tree - September 4, 2022
Vertical order traversal of a binary tree - September 4, 2022
Recover binary search tree - September 4, 2022
Construct binary tree from inorder and postorder traversal - September 4, 2022
delete-node-in-a-bst - September 4, 2022
Populating next right pointers in each node II - September 4, 2022
Balance a binary search tree - September 3, 2022
Average of levels in binary tree - September 2, 2022
Sum root to leaf numbers - September 2, 2022
N-ary tree level order traversal - September 1, 2022
Construct binary tree from preorder and postorder traversal - August 21, 2022
Cousins in binary tree - August 21, 2022
Convert sorted array to binary search tree - August 10, 2022
Kth smallest element in a bst - August 6, 2022
Validate binary search tree - August 6, 2022
Binary tree maximum path sum - August 6, 2022
Serialize and deserialize binary tree - August 6, 2022
My calendar I - August 3, 2022
Flatten binary tree to linked list - July 27, 2022
Lowest common ancestor of a binary tree - July 26, 2022
Count good nodes in binary tree - July 26, 2022
N-ary tree postorder traversal - July 20, 2022
Binary tree inorder traversal - July 20, 2022
N-ary tree preorder traversal - July 20, 2022
Binary tree postorder traversal - July 20, 2022
Binary tree preorder traversal - July 20, 2022
Path sum - July 19, 2022
Find largest value in each tree row - July 18, 2022
Lowest common ancestor of a binary search tree - July 18, 2022
Invert binary tree - July 14, 2022
Same tree - July 14, 2022
Diameter of binary tree - July 14, 2022
Balanced binary tree - July 14, 2022
Construct binary tree from preorder and inorder traversal - July 14, 2022
Maximum depth of n-ary tree - July 14, 2022
Maximum depth of binary tree - July 14, 2022
Subtree of another tree - July 14, 2022
Binary tree level order traversal - July 13, 2022
Binary tree right side view - July 11, 2022
