北叶青藤

摘要： 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 阅读全文

摘要： Given a string, your task is to count how many palindromic substrings in this string. The substrings with different start indexes or end indexes are c 阅读全文

摘要： Given a binary tree, return all duplicate subtrees. For each kind of duplicate subtrees, you only need to return the root node of any one of them. Two 阅读全文

摘要： On a single threaded CPU, we execute some functions. Each function has a unique id between 0 and N-1. We store logs in timestamp order that describe w 阅读全文

摘要： An image is represented by a 2-D array of integers, each integer representing the pixel value of the image (from 0 to 65535). Given a coordinate (sr, 阅读全文

摘要： We are given an array asteroids of integers representing asteroids in a row. For each asteroid, the absolute value represents its size, and the sign r 阅读全文

摘要： Given a char array representing tasks CPU need to do. It contains capital letters A to Z where different letters represent different tasks.Tasks could 阅读全文

摘要： Given a BST, remove an extra edge to make it BST. 7 / \ 5 9 / \ / 3 8 阅读全文

摘要： In this problem, a tree is an undirected graph that is connected and has no cycles. The given input is a graph that started as a tree with N nodes (wi 阅读全文

摘要： Given a string s, find the longest palindromic subsequence's length in s. You may assume that the maximum length of s is 1000. Example 1:Input: "bbbab 阅读全文