原创 Isomorphic Strings
Given two strings s and t, determine if they are isomorphic. Two strings are isomorphic if the characters in s can be r
2020-02-25 22:23:49
原创 Contains Duplicate
Given an array of integers, find if the array contains any duplicates. Your function should return true if any value ap
2020-02-25 22:23:07
原创 Compare Version Numbers
Compare two version numbers version1 and version2. If version1 > version2 return 1, if version1 < version2 return -1, o
2020-02-25 22:23:07
原创 Rotate Array
Rotate an array of n elements to the right by k steps. For example, with n = 7 and k = 3, the array [1,2,3,4,5,6,7] is
2020-02-25 22:23:07
原创 數據結構——散列表
什麼是散列表 散列表也叫做哈希表（hash table），這種數據結構提供了鍵和值的映射關係。根據key可以快速的查找他所匹配的value，時間複雜度接近於O(1)。 散列表的實現 散列表本質上就是一個數組，這
2020-02-25 22:23:07
原创 Min Stack
Design a stack that supports push, pop, top, and retrieving the minimum element in constant time. push(x) -- Push eleme
2020-02-25 22:23:07
原创 Reverse Bits
Reverse bits of a given 32 bits unsigned integer. For example, given input 43261596 (represented in binary as 000000101
2020-02-25 22:23:07
1
原创 Contains Duplicate II
Given an array of integers and an integer k, find out whether there are two distinct indices i and j in the array such
2020-02-25 22:23:07
原创 Excel Sheet Column Number
Related to question Excel Sheet Column Title Given a column title as appear in an Excel sheet, return its corresponding
2020-02-25 22:23:07
原创 Excel Sheet Column Title
Given a positive integer, return its corresponding column title as appear in an Excel sheet. For example: 1 -> A
2020-02-25 22:23:07
原创 Intersection of Two Linked Lists
Write a program to find the node at which the intersection of two singly linked lists begins. For example, the followin
2020-02-25 22:23:07
原创 Implement Stack using Queues
Implement the following operations of a stack using queues. push(x) -- Push element x onto stack.pop() -- Removes the e
2020-02-25 22:23:07
2
原创 Number of 1 Bits
Write a function that takes an unsigned integer and returns the number of ’1' bits it has (also known as the Hamming w
2020-02-25 22:23:07
原创 Happy Number
Write an algorithm to determine if a number is "happy". A happy number is a number defined by the following process: St
2020-02-25 22:23:07
原创 Rectangle Area
Find the total area covered by two rectilinear rectangles in a 2D plane. Each rectangle is defined by its bottom left c
2020-02-25 22:23:07