摘要：
Problem LeetCode Given the root of a tree, you are asked to find the most frequent subtree sum. The subtree sum of a node is defined as the sum of all 阅读全文
摘要：
Problem LeetCode Given an n-ary tree, return the level order traversal of its nodes' values. Nary-Tree input serialization is represented in their lev 阅读全文
摘要：
Problem LeetCode Given a binary search tree (BST), find the lowest common ancestor (LCA) of two given nodes in the BST. According to the definition of 阅读全文
摘要：
Problem LeetCode Given the root of a binary tree, return the postorder traversal of its nodes' values. Example 1: Input: root = [1,null,2,3] Output: [ 阅读全文
摘要：
Problem LeetCode Given the root of a binary tree, return the postorder traversal of its nodes' values. Example 1: Input: root = [1,null,2,3] Output: [ 阅读全文
摘要：
Problem LeetCode Given the root of a binary tree, return the preorder traversal of its nodes' values. Example 1: Input: root = [1,null,2,3] Output: [1 阅读全文
摘要：
Problem LeetCode Given a binary tree containing digits from 0-9 only, each root-to-leaf path could represent a number. An example is the root-to-leaf 阅读全文
摘要：
Problem LeetCode Given a binary tree, return the zigzag level order traversal of its nodes' values. (ie, from left to right, then right to left for th 阅读全文
摘要：
Problem LeetCode Given a complete binary tree, count the number of nodes. Note: Definition of a complete binary tree from Wikipedia: In a complete bin 阅读全文
摘要：
Problem LeetCode Given the root of a Binary Search Tree (BST), convert it to a Greater Tree such that every key of the original BST is changed to the 阅读全文