Split Array Largest Sum

Given an array which consists of non-negative integers and an integer m, you can split the array into m non-empty continuous subarrays. Write an algorithm to minimize the largest sum among these m subarrays.
（分割数组的最大值最小）

Meeting Rooms II

给定一系列的会议时间间隔intervals，包括起始和结束时间[[s1,e1],[s2,e2],…]，找到所需的最小的会议室数量。
（区间重叠最多部分）

Maximum Product of Three Numbers

Given an integer array, find three numbers whose product is maximum and output the maximum product.
（从数组中找出乘积最大的3个数）

Convert Binary Search Tree to Sorted Doubly Linked List

Convert a BST to a sorted circular doubly-linked list in-place. Think of the left and right pointers as synonymous to the previous and next pointers in a doubly-linked list.
（将二叉搜索树转换为一个有序的双向链表）

Validate Stack Sequences

Given two sequences pushed and popped with distinct values, return true if and only if this could have been the result of a sequence of push and pop operations on an initially empty stack.
（判断有效的栈压入、压出序列）

Note:

1. 0 <= pushed.length == popped.length <= 1000
2. 0 <= pushed[i], popped[i] < 1000
3. pushed is a permutation of popped.
4. pushed and popped have distinct values.

Knapsack Problem

背包问题

Perfect Squares

Given a positive integer n, find the least number of perfect square numbers (for example, 1, 4, 9, 16, …) which sum to n.
（将一个正整数分为干个平方数的和，使得平方数个数最少）

Integer to English Words

Convert a non-negative integer to its english words representation. Given input is guaranteed to be less than 2^31 - 1.
（读数值）

Ugly Number II

Write a program to find the n-th ugly number. Ugly numbers are positive numbers whose prime factors only include 2, 3, 5.
（第 n 个丑数）

Closest Pair of Points（平面最近点对）