摘要：
Write an algorithm to determine if a number is "happy".A happy number is a number defined by the following process: Starting with any positive integer... 阅读全文
摘要：
The string"PAYPALISHIRING"is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font fo... 阅读全文
摘要：
Find the total area covered by tworectilinearrectangles in a2Dplane.Each rectangle is defined by its bottom left corner and top right corner as shown ... 阅读全文
摘要：
217 - Contains DuplicateGiven an array of integers, find if the array contains any duplicates. Your function should return true if any value appears a... 阅读全文
摘要：
Invert a binary tree. 4 / \ 2 7 / \ / \1 3 6 9 to 4 / \ 7 2 / \ / \9 6 3 1Notice:Google: 90% of our engineers... 阅读全文
摘要：
Given two stringssandt, write a function to determine iftis an anagram ofs.For example,s= "anagram",t= "nagaram", return true.s= "rat",t= "car", retur... 阅读全文
摘要：
232 - Implement Queue using StacksImplement the following operations of a queue using stacks.push(x) -- Push element x to the back of queue.pop() -- R... 阅读全文