412. Fizz Buzz
题目给你一个整数 n ，找出从 1 到 n 各个整数的 Fizz Buzz 表示，并用字符串数组 answer（下标从 1 开始）返回结果，其中：
answer[i] == "FizzBuzz" 如果 i 同时是 3 和 5 的倍数。
answer[i] == "Fi
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999. 车的可用捕获量
题目在一个 8 x 8 的棋盘上，有一个白色的车（Rook），用字符 'R' 表示。棋盘上还可能存在空方块，白色的象（Bishop）以及黑色的卒（pawn），分别用字符 '.'，'B' 和 'p' 表示。不难看出，大写字符表示的是白棋，
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1056. 易混淆数
题目给定一个数字 N，当它满足以下条件的时候返回 true：
原数字旋转 180° 以后可以得到新的数字。
如 0, 1, 6, 8, 9 旋转 180° 以后，得到了新的数字 0, 1, 9, 8, 6 。
2, 3, 4, 5, 7 旋转 180° 后，得到的不是数字。
易混淆数 (confus
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759. Employee Free Time
题目
We are given a list schedule of employees, which represents the working time for each employee.
Each employee has a list of non-overlapping Interv
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215. Kth Largest Element in an Array
题目Find the kth largest element in an unsorted array. Note that it is the kth largest element in the sorted order, not the kth distinct element.
示例1:12
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355. Design Twitter
题目Design a simplified version of Twitter where users can post tweets, follow/unfollow another user and is able to see the 10 most recent tweets i
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347. Top K Frequent Elements
题目Given a non-empty array of integers, return the *k* most frequent elements.
示例1:12Input: nums = [1,1,1,2,2,3], k = 2Output: [1,2]
示例2：12Input: nums
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707. Design Linked List
题目
You are given two non-empty linked lists representing two non-negative integers. The most significant digit comes first and each of their nodes con
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451. Sort Characters By Frequency
题目Given a string, sort it in decreasing order based on the frequency of characters.
示例1:123456789Input:"tree"Output:"eert"Explanat
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707. Design Linked List
题目Design your implementation of the linked list. You can choose to use the singly linked list or the doubly linked list. A node in a singly linked lis
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