Given a binary tree, return the tilt of the whole tree. The tilt of a tree node is defined as the absolute difference between the sum of all left subt ...

Given an integer array with no duplicates. A maximum tree building on this array is defined as follow: The root is the maximum number in the array. T ...

For an undirected graph with tree characteristics, we can choose any node as the root. The result graph is then a rooted tree. Among all possible root ...

Given a binary search tree and a node in it, find the in-order successor of that node in the BST. If the given node has no in-order successor in the t ...

Given the root node of a binary search tree, return the sum of values of all nodes with value between L and R (inclusive). The binary search tree is g ...

Given a binary search tree (BST) with duplicates, find all the mode(s) (the most frequently occurred element) in the given BST. Assume a BST is define ...

Given a binary tree, find the lowest common ancestor (LCA) of two given nodes in the tree. According to the definition of LCA on Wikipedia: “The lowes ...

Given a binary search tree (BST), find the lowest common ancestor (LCA) of two given nodes in the BST. According to the definition of LCA on Wikipedia ...

Serialization is the process of converting a data structure or object into a sequence of bits so that it can be stored in a file or memory buffer, or ...

Serialization is the process of converting a data structure or object into a sequence of bits so that it can be stored in a file or memory buffer, or ...