Suppose you have a random list of people standing in a queue. Each person is described by a pair of integers(h, k), where h is the height of the person and k is the number of people in front of this person who have a height greater than or equal to h…

这题的关键点在于对数组的重排序方法,高度先由高到低排列不会影响第二个参数,因为list.add的方法在指定index后面插入,因此对于同高的人来说需要对第二个参数由低到高排,具体代码如下 public class Solution { public int[][] reconstructQueue(int[][] people) { Arrays.sort(people, new Comparator<int[]>() { public int compare(int[] o1, int[]…

Implement the following operations of a queue using stacks. push(x) -- Push element x to the back of queue. pop() -- Removes the element from in front of queue. peek() -- Get the front element. empty() -- Return whether the queue is empty. Notes: You…

用python实现多级排序,可以像C语言那样写个my_cmp,然后在sort的时候赋给参数cmp即可 但实际上,python处理cmp 是很慢的,因为每次比较都会调用my_cmp:而使用key和reverse就快得多,因为只需要在排序开始时处理一次即可,因此在排序的时候能不用cmp就尽量不用 另外可以用operator函数中的itemgetter,和attrgetter实现基于key的(多级)排序: from operator import itemgetter, attrgetter sort…

一天一道LeetCode 本系列文章已全部上传至我的github,地址:ZeeCoder's Github 欢迎大家关注我的新浪微博,我的新浪微博 欢迎转载,转载请注明出处 (一)题目 Implement the following operations of a queue using stacks. push(x) – Push element x to the back of queue. pop() – Removes the element from in front of queue…

Design your implementation of the circular queue. The circular queue is a linear data structure in which the operations are performed based on FIFO (First In First Out) principle and the last position is connected back to the first position to make a…

这是悦乐书的第195次更新,第201篇原创 01 看题和准备 今天介绍的是LeetCode算法题中Easy级别的第57题(顺位题号是232).使用栈实现队列的以下操作. push(x) - 将元素x推送到队列的后面. pop() - 从队列前面删除元素. peek() - 获取前面的元素. empty() - 返回队列是否为空. 例如: MyQueue queue = new MyQueue(); queue.push(1); queue.push(2); queue.peek(); //返回1…

题目链接:https://leetcode.com/problems/implement-queue-using-stacks/ 题目:Implement the following operations of a queue using stacks. push(x) -- Push element x to the back of queue. pop() -- Removes the element from in front of queue. peek() -- Get the fro…

LeetCode 622:设计循环队列 Design Circular Queue 首先来看看队列这种数据结构: 队列:先入先出的数据结构 在 FIFO 数据结构中,将首先处理添加到队列中的第一个元素. 如上图所示,队列是典型的 FIFO 数据结构.插入(insert)操作也称作入队(enqueue),新元素始终被添加在队列的末尾. 删除(delete)操作也被称为出队(dequeue). 你只能移除第一个元素. 队列 - 实现 为了实现队列,我们可以使用动态数组和指向队列头部的索引. 如上所述…

A string S of lowercase letters is given.  Then, we may make any number of moves. In each move, we choose one of the first K letters (starting from the left), remove it, and place it at the end of the string. Return the lexicographically smallest str…