Given a positive integer, return its corresponding column title as appea...

A peak element is an element that is greater than its neighbors.Given an...

Given an array of integers that is already sorted in ascending order, fi...

Follow up for "Find Minimum in Rotated Sorted Array":What if duplicates ...

Suppose an array sorted in ascending order is rotated at some pivot unkn...

Design a stack that supports push, pop, top, and retrieving the minimum ...

Sort a linked list using insertion sort. 分析 使用插入排序，排序一个链表。先列出首节点，然后依次对比节...

Given a linked list, return the node where the cycle begins. If there is...

Given a linked list, determine if it has a cycle in it. Follow up:Can yo...