摘要：
You're given strings J representing the types of stones that are jewels, and S representing the stones you have. Each character in S is a type of ston 阅读全文
摘要：
On a 2x3 board, there are 5 tiles represented by the integers 1 through 5, and an empty square represented by 0. A move consists of choosing 0 and a 4 阅读全文
摘要：
Given a root node reference of a BST and a key, delete the node with the given key in the BST. Return the root node reference (possibly updated) of th 阅读全文