Find the $n$ th digit of the infinite integer sequence 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, … Note:n is positive and will fit w...

Find the sum of all left leaves in a given binary tree. Example: 1234567 3 / \ 9 20 / \ 15 7There are two left...

A sequence of number is called arithmetic if it consists of at least three elements and if the difference between any two con...

A frog is crossing a river. The river is divided into x units and at each unit there may or may not exist a stone. The frog c...

Intro常用的人脸特征向量生成的方法都存在一定的问题： 1. 基于分类的方法 - 网络中用于分类的全连接层W随着参与训练的identity的增加而增加，使得网络参数量大。 - 在open-set的情景下，学习到的人脸特征区分力不够。 2...

Given an array which consists of non-negative integers and an integer m, you can split the array into m non-empty continuous ...

Given a string which consists of lowercase or uppercase letters, find the length of the longest palindromes that can be built...

Given an m x n matrix of non-negative integers representing the height of each unit cell in a continent, the “Pacific ocean” ...

Given a non-empty array of integers, return the third maximum number in this array. If it does not exist, return the maximum ...

Given two non-negative integers num1and num2 represented as string, return the sum of num1 and num2. Note: The length of bot...