# Posts with tag 'tree'

## Binary Search Tree Typo

less than 1 minute read

You are given a binary tree root which is almost a binary search tree except two nodes’ values have been swapped. Return the original binary search tree.

## Largest Binary Search Subtree in Value

less than 1 minute read

Given a binary tree root, return the largest sum of a subtree that is also a binary search tree.

## Longest Tree Path

less than 1 minute read

Given a binary tree root, return the longest path between any two nodes in the tree.

## Top View of a Tree

less than 1 minute read

Given a binary tree root, return the top view of the tree, sorted left-to-right.

## Enlarge BST

less than 1 minute read

Given a binary search tree root, replace every node’s value v by its value plus the sum of all other values in the tree that are greater than v.

## Split Tree to Maximize Product

less than 1 minute read

Given a binary tree root, consider deleting an edge in the tree so that the tree becomes disjoint with two trees. Then, take the sum of each subtree and mult...

## Most Frequent Subtree Sum

less than 1 minute read

Given a binary tree root, find the most frequent subtree sum. The subtree sum of a node is the sum of all values under a node, including the node itself. You...

## Lowest Common Ancestor

less than 1 minute read

Given a binary tree root, and integers a and b, find the value of the lowest node that has a and b as descendants. A node can be a descendant of itself.

## Largest Tree Sum Path

less than 1 minute read

Given a binary tree root, return the largest sum of any path between any two nodes.

## Longest Tree Sum Path From Root to Leaf

less than 1 minute read

Given a binary tree root, return the sum of the longest path from the root to a leaf node. If there are two equally long paths, return the larger sum.

## Linked List to ZigZag Tree Path

less than 1 minute read

Given a singly linked list node, convert it to a binary tree path using these rules:

## Largest Root to Leaf Sum

less than 1 minute read

Given the root to a binary tree root, return the largest sum of any path that goes from the root to a leaf.

## Partition Tree

less than 1 minute read

Given the root to a binary tree root, return a list of two numbers where the first number is the number of leaves in the tree and the second number is the nu...

## Longest Even Value Path

less than 1 minute read

Given a binary tree root, return the longest path consisting of even values between any two nodes in the tree.

## Count Nodes in Complete Binary Tree

less than 1 minute read

Given a complete binary tree root, return the number of nodes in the tree.

## Vertical Lines in Binary Tree

Given a binary tree root, return the number of unique vertical lines that can be drawn such that every node has a line intersecting it. Each left child is an...

## Univalue Tree

less than 1 minute read

Given a binary tree root, return whether all values in the tree are the same.

## Univalue Tree Count

less than 1 minute read

A univalue tree is a tree where all nodes under it have the same value.

## Twin Trees

Given two binary trees, root0 and root1, return whether their structure and values are equal.

## Tree with Distinct Parities

less than 1 minute read

Given a binary tree root, return the number of perfect nodes. A perfect node has two properties:

## Tree Traversal

You are given a tree root and a list of strings moves consisting of "RIGHT", "LEFT" and "UP". Starting from root, traverse the tree by performing each move i...

## Tree Sum

less than 1 minute read

Given a binary tree root, return the sum of all values in the tree.

## Tree Pruning

less than 1 minute read

Given a binary tree root, prune the tree so that subtrees containing all 0s are removed.

## Tree From Pre/Inorder Traversals

less than 1 minute read

Given a list of unique integers preorder and another list of unique integers inorder, representing the pre-order and in-order traversals of a binary tree, re...

## Tree Coloring

You are given a binary tree root where the value of each node represents its color. In the tree there are at most 2 colors. Return whether it’s possible to s...

## Symmetric Binary Tree

less than 1 minute read

Given the root to a binary tree root, return whether it is symmetric.

## Swappable Trees

less than 1 minute read

Given two trees root0 and root1, return whether you can transform root0 into root1 by swapping any node’s left and right subtrees any number of times.

## Sum Tree

less than 1 minute read

Given a binary tree root, return whether for every node in the tree other than the leaves, its value is equal to the sum of its left child’s value and its ri...

## Sum of Two Numbers in BSTs

You are given two binary search trees a and b and an integer target. Return whether there’s a number in a and a number in b such that their sum equals to tar...

## Sum of the Deepest Nodes

less than 1 minute read

Given a binary tree root, find the sum of the deepest node values.

## Sum of Right Leaves

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Given a binary tree root, return the sum of all leaves that are right children.

## Sum of Nodes with Even Grandparent Values

less than 1 minute read

Given a binary tree root, return the sum of all node values whose grandparents have an even value.

## Sum of Digit Paths in a Tree

less than 1 minute read

You are given a binary tree root with each node containing single digits from 0 to 9. Each path from the root to the leaf represents a number with its digits...

## Subtree

less than 1 minute read

You are given two binary trees root, and target. Return whether target is a subtree of root — that is, whether there’s a node in root that is identically sam...

## Subtree with Maximum Average

Given a binary tree root, return the maximum average value of a subtree. A subtree is defined to be some node in root including all of its descendants. A sub...

## Sibling Tree Value

You are given an integer k and a binary search tree root, where each node is either a leaf or contains 2 children.

## Second Place

less than 1 minute read

Given a binary tree root, return the depth of the second deepest leaf. Note that if there are multiple deepest leaves, the second deepest leaf is the next hi...

## Search in a Virtually Complete Binary Tree

Consider a complete binary tree of n nodes whose values are 1 to n. The root has value of 1, its left child is 2 and its right child is 3. In general, nodes’...

## Search in a Binary Search Tree

less than 1 minute read

Given a binary search tree root and an integer val, determine whether val is in the tree.

## Palindromic Tree

less than 1 minute read

Given a binary tree root where each node contains a digit from 0-9, return whether its in-order traversal is a palindrome.

## Only Child

less than 1 minute read

Given a binary tree root, return the number of nodes that are an only child. A node x is an only child if its parent has exactly one child (x).

## Next Node on Its Right

You are given a binary tree root containing unique values, and an integer target. Find the node with value target and return the node that’s directly right o...

## Merging Binary Trees

Given two binary trees node0 and node1, return a merge of the two trees where each value is equal to the sum of the values of the corresponding nodes of the ...

## List to Binary Search Tree

less than 1 minute read

Given a sorted list nums of size n, construct a binary search tree by

## Linked List to Binary Search Tree

less than 1 minute read

Given a sorted linked list node of size n, construct a binary search tree by

## Level Order Traversal

less than 1 minute read

Given a binary tree root return a level order traversal of the node values.

## Level Order Binary Tree to Linked List

less than 1 minute read

Given a binary tree root, convert it to a singly linked list using level order traversal.

## Level Order Alternating

less than 1 minute read

Given a binary tree root, return values of the nodes in each level, alternating from going left-to-right and right-to-left.

## Leftmost Deepest Tree Node

less than 1 minute read

Given a binary tree root, find the value of the deepest node. If there’s more than one deepest node, then return the leftmost one.

## Left Side View of a Tree

less than 1 minute read

Given a binary tree root, return the leftmost node’s value on each level of the tree.

## Leaves in Same Level

less than 1 minute read

Given a binary tree root, return whether all leaves are at the same level.

## Leaf Equivalent Trees

less than 1 minute read

Given two binary trees root0 and root1, return whether the sequence of leaves left-to-right in both trees are the same.

## Kth Smallest in a Binary Search Tree

less than 1 minute read

Given a binary search tree root, and k return the kth (0-indexed) smallest value in root. It is guaranteed that the tree has at least k + 1 nodes.

## Invert Tree

less than 1 minute read

Given a binary tree root, invert it so that its left subtree and right subtree are swapped and the children are recursively inverted.

## Inorder Traversal

less than 1 minute read

Given a binary tree root, return an inorder traversal of root as a list.

## Inorder Successor

Given a binary search tree root containing unique values, and an integer t, return the value of the inorder successor of t. That is, return the smallest valu...

## Height Balanced Tree

less than 1 minute read

Given the root of a binary tree, return whether its height is balanced. That is, for every node in the tree, the absolute difference of the height of its lef...

## Elephant Tree

less than 1 minute read

Given a binary tree root, return the same tree except every node’s value is replaced by its original value plus all of the sums of its left and right subtrees.

## Diagonal Tree Traversal

less than 1 minute read

Given a binary tree root, return the sum of each of the diagonals in the tree starting from the top to bottom right.

## Delete Even Leaves

less than 1 minute read

Given a binary tree root, repeatedly delete all leaves that have even values. That is, if after deletions, a node becomes a leaf with an even value, it too s...

## Cutting Binary Search Tree

less than 1 minute read

Given a binary search tree root, an integer lo, and another an integer hi, remove all nodes that are not between [lo, hi] inclusive.

## Counting Maximal Value Roots in Binary Tree

less than 1 minute read

Given a binary tree root, count and return the number of nodes where its value is greater than or equal to the values of all of its descendants.

## Count BST Nodes in a Range

less than 1 minute read

Given a binary search tree root, and integers lo and hi, return the count of all nodes in root whose values are between [lo, hi] (inclusive).

## Convert to Full Binary Tree

less than 1 minute read

Given a binary tree root, remove all nodes with only one child.

## Complete Binary Tree

less than 1 minute read

Given a binary tree root, return whether it’s a complete binary tree.

## Binary Tree to Linked List

less than 1 minute read

Given a binary tree root, convert it to a singly linked list using an inorder traversal.

## Binary Search Tree Validation

less than 1 minute read

Given a binary tree root, return whether it’s a binary search tree. A binary tree node is a binary search tree if :