Data Structures > Tree

Binary Indexed Tree

• 3382. Maximum Area Rectangle With Point Constraints II
• 3380. Maximum Area Rectangle With Point Constraints I
• 3245. Alternating Groups III
• 3187. Peaks in Array
• 3161. Block Placement Queries
• 3109. Find the Index of Permutation
• 3072. Distribute Elements Into Two Arrays II
• 3009. Maximum Number of Intersections on the Chart
• 2940. Find Building Where Alice and Bob Can Meet
• 2926. Maximum Balanced Subsequence Sum
• 2921. Maximum Profitable Triplets With Increasing Prices II
• 2916. Subarrays Distinct Element Sum of Squares II
• 2907. Maximum Profitable Triplets With Increasing Prices I
• 2736. Maximum Sum Queries
• 2659. Make Array Empty
• 2552. Count Increasing Quadruplets
• 2519. Count the Number of K-Big Indices
• 2426. Number of Pairs Satisfying Inequality
• 2424. Longest Uploaded Prefix
• 2407. Longest Increasing Subsequence II
• 2286. Booking Concert Tickets in Groups
• 2250. Count Number of Rectangles Containing Each Point
• 2193. Minimum Number of Moves to Make Palindrome
• 2179. Count Good Triplets in an Array
• 2031. Count Subarrays With More Ones Than Zeros
• 1964. Find the Longest Valid Obstacle Course at Each Position
• 1756. Design Most Recently Used Queue
• 1649. Create Sorted Array through Instructions
• 1505. Minimum Possible Integer After at Most K Adjacent Swaps On Digits
• 1409. Queries on a Permutation With Key
• 1395. Count Number of Teams
• 1157. Online Majority Element In Subarray
• 683. K Empty Slots
• 673. Number of Longest Increasing Subsequence
• 493. Reverse Pairs
• 406. Queue Reconstruction by Height
• 327. Count of Range Sum
• 315. Count of Smaller Numbers After Self
• 308. Range Sum Query 2D - Mutable
• 307. Range Sum Query - Mutable
• 218. The Skyline Problem

Binary Search Tree

• 2476. Closest Nodes Queries in a Binary Search Tree
• 1902. Depth of BST Given Insertion Order
• 1586. Binary Search Tree Iterator II
• 1569. Number of Ways to Reorder Array to Get Same BST
• 1382. Balance a Binary Search Tree
• 1373. Maximum Sum BST in Binary Tree
• 1305. All Elements in Two Binary Search Trees
• 1214. Two Sum BSTs
• 1038. Binary Search Tree to Greater Sum Tree
• 1008. Construct Binary Search Tree from Preorder Traversal
• 938. Range Sum of BST
• 897. Increasing Order Search Tree
• 783. Minimum Distance Between BST Nodes
• 776. Split BST
• 703. Kth Largest Element in a Stream
• 701. Insert into a Binary Search Tree
• 700. Search in a Binary Search Tree
• 669. Trim a Binary Search Tree
• 653. Two Sum IV - Input is a BST
• 538. Convert BST to Greater Tree
• 530. Minimum Absolute Difference in BST
• 510. Inorder Successor in BST II
• 501. Find Mode in Binary Search Tree
• 450. Delete Node in a BST
• 449. Serialize and Deserialize BST
• 426. Convert Binary Search Tree to Sorted Doubly Linked List
• 333. Largest BST Subtree
• 285. Inorder Successor in BST
• 272. Closest Binary Search Tree Value II
• 270. Closest Binary Search Tree Value
• 255. Verify Preorder Sequence in Binary Search Tree
• 235. Lowest Common Ancestor of a Binary Search Tree
• 230. Kth Smallest Element in a BST
• 173. Binary Search Tree Iterator
• 109. Convert Sorted List to Binary Search Tree
• 108. Convert Sorted Array to Binary Search Tree
• 99. Recover Binary Search Tree
• 98. Validate Binary Search Tree
• 96. Unique Binary Search Trees
• 95. Unique Binary Search Trees II

Binary Tree

• 3319. K-th Largest Perfect Subtree Size in Binary Tree
• 3157. Find the Level of Tree with Minimum Sum
• 2792. Count Nodes That Are Great Enough
• 2773. Height of Special Binary Tree
• 2764. Is Array a Preorder of Some ‌Binary Tree
• 2689. Extract Kth Character From The Rope Tree
• 2673. Make Costs of Paths Equal in a Binary Tree
• 2641. Cousins in Binary Tree II
• 2583. Kth Largest Sum in a Binary Tree
• 2509. Cycle Length Queries in a Tree
• 2476. Closest Nodes Queries in a Binary Search Tree
• 2471. Minimum Number of Operations to Sort a Binary Tree by Level
• 2458. Height of Binary Tree After Subtree Removal Queries
• 2445. Number of Nodes With Value One
• 2415. Reverse Odd Levels of Binary Tree
• 2385. Amount of Time for Binary Tree to Be Infected
• 2331. Evaluate Boolean Binary Tree
• 2313. Minimum Flips in Binary Tree to Get Result
• 2265. Count Nodes Equal to Average of Subtree
• 2236. Root Equals Sum of Children
• 2196. Create Binary Tree From Descriptions
• 2096. Step-By-Step Directions From a Binary Tree Node to Another
• 2049. Count Nodes With the Highest Score
• 2005. Subtree Removal Game with Fibonacci Tree
• 1973. Count Nodes Equal to Sum of Descendants
• 1932. Merge BSTs to Create Single BST
• 1902. Depth of BST Given Insertion Order
• 1740. Find Distance in a Binary Tree
• 1676. Lowest Common Ancestor of a Binary Tree IV
• 1666. Change the Root of a Binary Tree
• 1660. Correct a Binary Tree
• 1650. Lowest Common Ancestor of a Binary Tree III
• 1644. Lowest Common Ancestor of a Binary Tree II
• 1628. Design an Expression Tree With Evaluate Function
• 1612. Check If Two Expression Trees are Equivalent
• 1609. Even Odd Tree
• 1602. Find Nearest Right Node in Binary Tree
• 1597. Build Binary Expression Tree From Infix Expression
• 1586. Binary Search Tree Iterator II
• 1569. Number of Ways to Reorder Array to Get Same BST
• 1530. Number of Good Leaf Nodes Pairs
• 1485. Clone Binary Tree With Random Pointer
• 1469. Find All The Lonely Nodes
• 1457. Pseudo-Palindromic Paths in a Binary Tree
• 1448. Count Good Nodes in Binary Tree
• 1430. Check If a String Is a Valid Sequence from Root to Leaves Path in a Binary Tree
• 1382. Balance a Binary Search Tree
• 1379. Find a Corresponding Node of a Binary Tree in a Clone of That Tree
• 1373. Maximum Sum BST in Binary Tree
• 1372. Longest ZigZag Path in a Binary Tree
• 1367. Linked List in Binary Tree
• 1361. Validate Binary Tree Nodes
• 1339. Maximum Product of Splitted Binary Tree
• 1325. Delete Leaves With a Given Value
• 1315. Sum of Nodes with Even-Valued Grandparent
• 1305. All Elements in Two Binary Search Trees
• 1302. Deepest Leaves Sum
• 1261. Find Elements in a Contaminated Binary Tree
• 1214. Two Sum BSTs
• 1161. Maximum Level Sum of a Binary Tree
• 1145. Binary Tree Coloring Game
• 1123. Lowest Common Ancestor of Deepest Leaves
• 1120. Maximum Average Subtree
• 1110. Delete Nodes And Return Forest
• 1104. Path In Zigzag Labelled Binary Tree
• 1080. Insufficient Nodes in Root to Leaf Paths
• 1038. Binary Search Tree to Greater Sum Tree
• 1028. Recover a Tree From Preorder Traversal
• 1026. Maximum Difference Between Node and Ancestor
• 1022. Sum of Root To Leaf Binary Numbers
• 1008. Construct Binary Search Tree from Preorder Traversal
• 998. Maximum Binary Tree II
• 993. Cousins in Binary Tree
• 988. Smallest String Starting From Leaf
• 987. Vertical Order Traversal of a Binary Tree
• 979. Distribute Coins in Binary Tree
• 971. Flip Binary Tree To Match Preorder Traversal
• 968. Binary Tree Cameras
• 965. Univalued Binary Tree
• 958. Check Completeness of a Binary Tree
• 951. Flip Equivalent Binary Trees
• 938. Range Sum of BST
• 919. Complete Binary Tree Inserter
• 897. Increasing Order Search Tree
• 894. All Possible Full Binary Trees
• 889. Construct Binary Tree from Preorder and Postorder Traversal
• 872. Leaf-Similar Trees
• 865. Smallest Subtree with all the Deepest Nodes
• 863. All Nodes Distance K in Binary Tree
• 814. Binary Tree Pruning
• 783. Minimum Distance Between BST Nodes
• 776. Split BST
• 742. Closest Leaf in a Binary Tree
• 703. Kth Largest Element in a Stream
• 701. Insert into a Binary Search Tree
• 700. Search in a Binary Search Tree
• 687. Longest Univalue Path
• 671. Second Minimum Node In a Binary Tree
• 669. Trim a Binary Search Tree
• 666. Path Sum IV
• 663. Equal Tree Partition
• 662. Maximum Width of Binary Tree
• 655. Print Binary Tree
• 654. Maximum Binary Tree
• 653. Two Sum IV - Input is a BST
• 652. Find Duplicate Subtrees
• 637. Average of Levels in Binary Tree
• 623. Add One Row to Tree
• 617. Merge Two Binary Trees
• 606. Construct String from Binary Tree
• 572. Subtree of Another Tree
• 563. Binary Tree Tilt
• 549. Binary Tree Longest Consecutive Sequence II
• 545. Boundary of Binary Tree
• 543. Diameter of Binary Tree
• 538. Convert BST to Greater Tree
• 536. Construct Binary Tree from String
• 530. Minimum Absolute Difference in BST
• 515. Find Largest Value in Each Tree Row
• 513. Find Bottom Left Tree Value
• 510. Inorder Successor in BST II
• 508. Most Frequent Subtree Sum
• 501. Find Mode in Binary Search Tree
• 450. Delete Node in a BST
• 449. Serialize and Deserialize BST
• 437. Path Sum III
• 431. Encode N-ary Tree to Binary Tree
• 426. Convert Binary Search Tree to Sorted Doubly Linked List
• 404. Sum of Left Leaves
• 366. Find Leaves of Binary Tree
• 337. House Robber III
• 333. Largest BST Subtree
• 331. Verify Preorder Serialization of a Binary Tree
• 314. Binary Tree Vertical Order Traversal
• 298. Binary Tree Longest Consecutive Sequence
• 297. Serialize and Deserialize Binary Tree
• 285. Inorder Successor in BST
• 272. Closest Binary Search Tree Value II
• 270. Closest Binary Search Tree Value
• 257. Binary Tree Paths
• 255. Verify Preorder Sequence in Binary Search Tree
• 250. Count Univalue Subtrees
• 236. Lowest Common Ancestor of a Binary Tree
• 235. Lowest Common Ancestor of a Binary Search Tree
• 230. Kth Smallest Element in a BST
• 226. Invert Binary Tree
• 222. Count Complete Tree Nodes
• 199. Binary Tree Right Side View
• 173. Binary Search Tree Iterator
• 156. Binary Tree Upside Down
• 145. Binary Tree Postorder Traversal
• 144. Binary Tree Preorder Traversal
• 129. Sum Root to Leaf Numbers
• 124. Binary Tree Maximum Path Sum
• 117. Populating Next Right Pointers in Each Node II
• 116. Populating Next Right Pointers in Each Node
• 114. Flatten Binary Tree to Linked List
• 113. Path Sum II
• 112. Path Sum
• 111. Minimum Depth of Binary Tree
• 110. Balanced Binary Tree
• 109. Convert Sorted List to Binary Search Tree
• 108. Convert Sorted Array to Binary Search Tree
• 107. Binary Tree Level Order Traversal II
• 106. Construct Binary Tree from Inorder and Postorder Traversal
• 105. Construct Binary Tree from Preorder and Inorder Traversal
• 104. Maximum Depth of Binary Tree
• 103. Binary Tree Zigzag Level Order Traversal
• 102. Binary Tree Level Order Traversal
• 101. Symmetric Tree
• 100. Same Tree
• 99. Recover Binary Search Tree
• 98. Validate Binary Search Tree
• 96. Unique Binary Search Trees
• 95. Unique Binary Search Trees II
• 94. Binary Tree Inorder Traversal

Segment Tree

• 3501. Maximize Active Section with Trade II
• 3480. Maximize Subarrays After Removing One Conflicting Pair
• 3479. Fruits Into Baskets III
• 3477. Fruits Into Baskets II
• 3454. Separate Squares II
• 3420. Count Non-Decreasing Subarrays After K Operations
• 3410. Maximize Subarray Sum After Removing All Occurrences of One Element
• 3382. Maximum Area Rectangle With Point Constraints II
• 3380. Maximum Area Rectangle With Point Constraints I
• 3292. Minimum Number of Valid Strings to Form Target II
• 3291. Minimum Number of Valid Strings to Form Target I
• 3209. Number of Subarrays With AND Value of K
• 3187. Peaks in Array
• 3171. Find Subarray With Bitwise OR Closest to K
• 3165. Maximum Sum of Subsequence With Non-adjacent Elements
• 3161. Block Placement Queries
• 3117. Minimum Sum of Values by Dividing Array
• 3109. Find the Index of Permutation
• 3072. Distribute Elements Into Two Arrays II
• 2940. Find Building Where Alice and Bob Can Meet
• 2926. Maximum Balanced Subsequence Sum
• 2921. Maximum Profitable Triplets With Increasing Prices II
• 2916. Subarrays Distinct Element Sum of Squares II
• 2907. Maximum Profitable Triplets With Increasing Prices I
• 2736. Maximum Sum Queries
• 2659. Make Array Empty
• 2569. Handling Sum Queries After Update
• 2519. Count the Number of K-Big Indices
• 2426. Number of Pairs Satisfying Inequality
• 2424. Longest Uploaded Prefix
• 2407. Longest Increasing Subsequence II
• 2286. Booking Concert Tickets in Groups
• 2276. Count Integers in Intervals
• 2213. Longest Substring of One Repeating Character
• 2179. Count Good Triplets in an Array
• 2158. Amount of New Area Painted Each Day
• 2080. Range Frequency Queries
• 2031. Count Subarrays With More Ones Than Zeros
• 1687. Delivering Boxes from Storage to Ports
• 1649. Create Sorted Array through Instructions
• 1622. Fancy Sequence
• 1521. Find a Value of a Mysterious Function Closest to Target
• 1505. Minimum Possible Integer After at Most K Adjacent Swaps On Digits
• 1395. Count Number of Teams
• 1157. Online Majority Element In Subarray
• 850. Rectangle Area II
• 732. My Calendar III
• 731. My Calendar II
• 729. My Calendar I
• 715. Range Module
• 699. Falling Squares
• 683. K Empty Slots
• 673. Number of Longest Increasing Subsequence
• 493. Reverse Pairs
• 406. Queue Reconstruction by Height
• 327. Count of Range Sum
• 315. Count of Smaller Numbers After Self
• 308. Range Sum Query 2D - Mutable
• 307. Range Sum Query - Mutable
• 218. The Skyline Problem

Tree

• 3486. Longest Special Path II
• 3425. Longest Special Path
• 3373. Maximize the Number of Target Nodes After Connecting Trees II
• 3372. Maximize the Number of Target Nodes After Connecting Trees I
• 3367. Maximize Sum of Weights after Edge Removals
• 3331. Find Subtree Sizes After Changes
• 3327. Check if DFS Strings Are Palindromes
• 3319. K-th Largest Perfect Subtree Size in Binary Tree
• 3313. Find the Last Marked Nodes in Tree
• 3249. Count the Number of Good Nodes
• 3241. Time Taken to Mark All Nodes
• 3203. Find Minimum Diameter After Merging Two Trees
• 3157. Find the Level of Tree with Minimum Sum
• 3068. Find the Maximum Sum of Node Values
• 3067. Count Pairs of Connectable Servers in a Weighted Tree Network
• 3004. Maximum Subtree of the Same Color
• 2973. Find Number of Coins to Place in Tree Nodes
• 2925. Maximum Score After Applying Operations on a Tree
• 2920. Maximum Points After Collecting Coins From All Nodes
• 2872. Maximum Number of K-Divisible Components
• 2867. Count Valid Paths in a Tree
• 2846. Minimum Edge Weight Equilibrium Queries in a Tree
• 2792. Count Nodes That Are Great Enough
• 2791. Count Paths That Can Form a Palindrome in a Tree
• 2773. Height of Special Binary Tree
• 2764. Is Array a Preorder of Some ‌Binary Tree
• 2689. Extract Kth Character From The Rope Tree
• 2673. Make Costs of Paths Equal in a Binary Tree
• 2646. Minimize the Total Price of the Trips
• 2641. Cousins in Binary Tree II
• 2603. Collect Coins in a Tree
• 2583. Kth Largest Sum in a Binary Tree
• 2581. Count Number of Possible Root Nodes
• 2538. Difference Between Maximum and Minimum Price Sum
• 2509. Cycle Length Queries in a Tree
• 2479. Maximum XOR of Two Non-Overlapping Subtrees
• 2477. Minimum Fuel Cost to Report to the Capital
• 2476. Closest Nodes Queries in a Binary Search Tree
• 2471. Minimum Number of Operations to Sort a Binary Tree by Level
• 2467. Most Profitable Path in a Tree
• 2458. Height of Binary Tree After Subtree Removal Queries
• 2445. Number of Nodes With Value One
• 2440. Create Components With Same Value
• 2421. Number of Good Paths
• 2415. Reverse Odd Levels of Binary Tree
• 2385. Amount of Time for Binary Tree to Be Infected
• 2378. Choose Edges to Maximize Score in a Tree
• 2368. Reachable Nodes With Restrictions
• 2331. Evaluate Boolean Binary Tree
• 2322. Minimum Score After Removals on a Tree
• 2313. Minimum Flips in Binary Tree to Get Result
• 2277. Closest Node to Path in Tree
• 2265. Count Nodes Equal to Average of Subtree
• 2246. Longest Path With Different Adjacent Characters
• 2236. Root Equals Sum of Children
• 2196. Create Binary Tree From Descriptions
• 2096. Step-By-Step Directions From a Binary Tree Node to Another
• 2049. Count Nodes With the Highest Score
• 2005. Subtree Removal Game with Fibonacci Tree
• 2003. Smallest Missing Genetic Value in Each Subtree
• 1993. Operations on Tree
• 1973. Count Nodes Equal to Sum of Descendants
• 1932. Merge BSTs to Create Single BST
• 1916. Count Ways to Build Rooms in an Ant Colony
• 1902. Depth of BST Given Insertion Order
• 1766. Tree of Coprimes
• 1740. Find Distance in a Binary Tree
• 1719. Number Of Ways To Reconstruct A Tree
• 1676. Lowest Common Ancestor of a Binary Tree IV
• 1666. Change the Root of a Binary Tree
• 1660. Correct a Binary Tree
• 1650. Lowest Common Ancestor of a Binary Tree III
• 1644. Lowest Common Ancestor of a Binary Tree II
• 1628. Design an Expression Tree With Evaluate Function
• 1617. Count Subtrees With Max Distance Between Cities
• 1612. Check If Two Expression Trees are Equivalent
• 1609. Even Odd Tree
• 1602. Find Nearest Right Node in Binary Tree
• 1600. Throne Inheritance
• 1597. Build Binary Expression Tree From Infix Expression
• 1586. Binary Search Tree Iterator II
• 1569. Number of Ways to Reorder Array to Get Same BST
• 1530. Number of Good Leaf Nodes Pairs
• 1522. Diameter of N-Ary Tree
• 1519. Number of Nodes in the Sub-Tree With the Same Label
• 1516. Move Sub-Tree of N-Ary Tree
• 1506. Find Root of N-Ary Tree
• 1490. Clone N-ary Tree
• 1485. Clone Binary Tree With Random Pointer
• 1483. Kth Ancestor of a Tree Node
• 1469. Find All The Lonely Nodes
• 1457. Pseudo-Palindromic Paths in a Binary Tree
• 1448. Count Good Nodes in Binary Tree
• 1443. Minimum Time to Collect All Apples in a Tree
• 1430. Check If a String Is a Valid Sequence from Root to Leaves Path in a Binary Tree
• 1382. Balance a Binary Search Tree
• 1379. Find a Corresponding Node of a Binary Tree in a Clone of That Tree
• 1377. Frog Position After T Seconds
• 1376. Time Needed to Inform All Employees
• 1373. Maximum Sum BST in Binary Tree
• 1372. Longest ZigZag Path in a Binary Tree
• 1367. Linked List in Binary Tree
• 1361. Validate Binary Tree Nodes
• 1339. Maximum Product of Splitted Binary Tree
• 1325. Delete Leaves With a Given Value
• 1315. Sum of Nodes with Even-Valued Grandparent
• 1305. All Elements in Two Binary Search Trees
• 1302. Deepest Leaves Sum
• 1273. Delete Tree Nodes
• 1261. Find Elements in a Contaminated Binary Tree
• 1257. Smallest Common Region
• 1245. Tree Diameter
• 1214. Two Sum BSTs
• 1161. Maximum Level Sum of a Binary Tree
• 1145. Binary Tree Coloring Game
• 1123. Lowest Common Ancestor of Deepest Leaves
• 1120. Maximum Average Subtree
• 1110. Delete Nodes And Return Forest
• 1104. Path In Zigzag Labelled Binary Tree
• 1080. Insufficient Nodes in Root to Leaf Paths
• 1038. Binary Search Tree to Greater Sum Tree
• 1028. Recover a Tree From Preorder Traversal
• 1026. Maximum Difference Between Node and Ancestor
• 1022. Sum of Root To Leaf Binary Numbers
• 1008. Construct Binary Search Tree from Preorder Traversal
• 998. Maximum Binary Tree II
• 993. Cousins in Binary Tree
• 988. Smallest String Starting From Leaf
• 987. Vertical Order Traversal of a Binary Tree
• 979. Distribute Coins in Binary Tree
• 971. Flip Binary Tree To Match Preorder Traversal
• 968. Binary Tree Cameras
• 965. Univalued Binary Tree
• 958. Check Completeness of a Binary Tree
• 951. Flip Equivalent Binary Trees
• 938. Range Sum of BST
• 919. Complete Binary Tree Inserter
• 897. Increasing Order Search Tree
• 894. All Possible Full Binary Trees
• 889. Construct Binary Tree from Preorder and Postorder Traversal
• 872. Leaf-Similar Trees
• 865. Smallest Subtree with all the Deepest Nodes
• 863. All Nodes Distance K in Binary Tree
• 834. Sum of Distances in Tree
• 814. Binary Tree Pruning
• 783. Minimum Distance Between BST Nodes
• 776. Split BST
• 742. Closest Leaf in a Binary Tree
• 703. Kth Largest Element in a Stream
• 701. Insert into a Binary Search Tree
• 700. Search in a Binary Search Tree
• 690. Employee Importance
• 687. Longest Univalue Path
• 671. Second Minimum Node In a Binary Tree
• 669. Trim a Binary Search Tree
• 666. Path Sum IV
• 663. Equal Tree Partition
• 662. Maximum Width of Binary Tree
• 655. Print Binary Tree
• 654. Maximum Binary Tree
• 653. Two Sum IV - Input is a BST
• 652. Find Duplicate Subtrees
• 637. Average of Levels in Binary Tree
• 623. Add One Row to Tree
• 617. Merge Two Binary Trees
• 606. Construct String from Binary Tree
• 590. N-ary Tree Postorder Traversal
• 589. N-ary Tree Preorder Traversal
• 582. Kill Process
• 572. Subtree of Another Tree
• 563. Binary Tree Tilt
• 559. Maximum Depth of N-ary Tree
• 558. Logical OR of Two Binary Grids Represented as Quad-Trees
• 549. Binary Tree Longest Consecutive Sequence II
• 545. Boundary of Binary Tree
• 543. Diameter of Binary Tree
• 538. Convert BST to Greater Tree
• 536. Construct Binary Tree from String
• 530. Minimum Absolute Difference in BST
• 515. Find Largest Value in Each Tree Row
• 513. Find Bottom Left Tree Value
• 510. Inorder Successor in BST II
• 508. Most Frequent Subtree Sum
• 501. Find Mode in Binary Search Tree
• 450. Delete Node in a BST
• 449. Serialize and Deserialize BST
• 437. Path Sum III
• 431. Encode N-ary Tree to Binary Tree
• 429. N-ary Tree Level Order Traversal
• 428. Serialize and Deserialize N-ary Tree
• 427. Construct Quad Tree
• 426. Convert Binary Search Tree to Sorted Doubly Linked List
• 404. Sum of Left Leaves
• 366. Find Leaves of Binary Tree
• 341. Flatten Nested List Iterator
• 337. House Robber III
• 333. Largest BST Subtree
• 331. Verify Preorder Serialization of a Binary Tree
• 314. Binary Tree Vertical Order Traversal
• 298. Binary Tree Longest Consecutive Sequence
• 297. Serialize and Deserialize Binary Tree
• 285. Inorder Successor in BST
• 272. Closest Binary Search Tree Value II
• 270. Closest Binary Search Tree Value
• 257. Binary Tree Paths
• 255. Verify Preorder Sequence in Binary Search Tree
• 250. Count Univalue Subtrees
• 236. Lowest Common Ancestor of a Binary Tree
• 235. Lowest Common Ancestor of a Binary Search Tree
• 230. Kth Smallest Element in a BST
• 226. Invert Binary Tree
• 222. Count Complete Tree Nodes
• 199. Binary Tree Right Side View
• 173. Binary Search Tree Iterator
• 156. Binary Tree Upside Down
• 145. Binary Tree Postorder Traversal
• 144. Binary Tree Preorder Traversal
• 129. Sum Root to Leaf Numbers
• 124. Binary Tree Maximum Path Sum
• 117. Populating Next Right Pointers in Each Node II
• 116. Populating Next Right Pointers in Each Node
• 114. Flatten Binary Tree to Linked List
• 113. Path Sum II
• 112. Path Sum
• 111. Minimum Depth of Binary Tree
• 110. Balanced Binary Tree
• 109. Convert Sorted List to Binary Search Tree
• 108. Convert Sorted Array to Binary Search Tree
• 107. Binary Tree Level Order Traversal II
• 106. Construct Binary Tree from Inorder and Postorder Traversal
• 105. Construct Binary Tree from Preorder and Inorder Traversal
• 104. Maximum Depth of Binary Tree
• 103. Binary Tree Zigzag Level Order Traversal
• 102. Binary Tree Level Order Traversal
• 101. Symmetric Tree
• 100. Same Tree
• 99. Recover Binary Search Tree
• 98. Validate Binary Search Tree
• 96. Unique Binary Search Trees
• 95. Unique Binary Search Trees II
• 94. Binary Tree Inorder Traversal