问题描述 Given a binary tree, find the left most element in the last row of the tree. Example 1: Input: 2 / \ 1 3 Output: 1 Example 2: Input: 1 / \ 2 3 / / \ 4 5 6 / 7 Output: 7 Note: You may assume the tree is not NULL. 算法分析: 逐层遍历二叉树是很经典的算法,常规的逐层遍历二叉树是使…

问题描述 You need to find the largest element in each row of a Binary Tree. Example: Input: 1 / \ 2 3 / \ \ 5 3 9 Output: [1, 3, 9] 算法分析 使用两个队列,逐层遍历二叉树的各个节点,每个队列中的节点都是同一层的节点,在遍历一层时,找出该层最大的节点值加入ArrayList中. Java算法实现: /** * Definition for a binary tree node…

Design a class to find the kth largest element in a stream. Note that it is the kth largest element in the sorted order, not the kth distinct element. Your KthLargest class will have a constructor which accepts an integer k and an integer array nums,…

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. For example, Given [3,2,1,5,6,4] and k = 2, return 5. Note: You may assume k is always valid, 1 ≤ k ≤ arr…

Given an array of size n, find the majority element. The majority element is the element that appears more than ⌊ n/2 ⌋ times. You may assume that the array is non-empty and the majority element always exist in the array. 题解:设置两个变量,一个是current,初始化为A[0…

Given n non-negative integers representing the histogram's bar height where the width of each bar is 1, find the area of largest rectangle in the histogram. Above is a histogram where width of each bar is 1, given height = [2,1,5,6,2,3]. The largest…

395. Longest Substring with At least K Repeating Characters Find the length of the longest substring T of a given string (consists of lowercase letters only) such that every character in T appears no less than k times. Example 1: Input: s = "aaabb&qu…

394. Decode String Given an encoded string, return it's decoded string. The encoding rule is: k[encoded_string], where the encoded_string inside the square brackets is being repeated exactly k times. Note that k is guaranteed to be a positive integer…

393. UTF-8 Validation A character in UTF8 can be from 1 to 4 bytes long, subjected to the following rules: For 1-byte character, the first bit is a 0, followed by its unicode code. For n-bytes character, the first n-bits are all one's, the n+1 bit is…

392. Is Subsequence Given a string s and a string t, check if s is subsequence of t. You may assume that there is only lower case English letters in both s and t. t is potentially a very long (length ~= 500,000) string, and s is a short string (<=100…

#391. Perfect Rectangle Given N axis-aligned rectangles where N > 0, determine if they all together form an exact cover of a rectangular region. Each rectangle is represented as a bottom-left point and a top-right point. For example, a unit square is…

# 390. Elimination Game There is a list of sorted integers from 1 to n. Starting from left to right, remove the first number and every other number afterward until you reach the end of the list. Repeat the previous step again, but this time from righ…

注意multiset的一个bug: multiset带一个参数的erase函数原型有两种.一是传递一个元素值,如上面例子代码中,这时候删除的是集合中所有值等于输入值的元素,并且返回删除的元素个数:另外一种是传递一个指向某个元素的iterator,这时候删除的就是这个对应的元素,无返回值. https://www.cnblogs.com/lakeone/p/5600494.html 删除的时候一定不能删除指针,只能删除迭代器 leetcode那个题就是在这个地方出错的: Input: [3,2,3…

传送门 有一个整数数组,请你根据快速排序的思路,找出数组中第K大的数. 给定一个整数数组a,同时给定它的大小n和要找的K(K在1到n之间),请返回第K大的数,保证答案存在. 测试样例: [1,3,5,2,2],5,3 返回:2 note: 注意手写快排的时候: while(i < j) { while(j > i && a[j] > a[left]) j--; while(i < j && a[i] <= a[left]) i++; if(i…

这是悦乐书的第296次更新,第315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164题(顺位题号是703).设计一个类来查找流中第k个最大元素.请注意,它是排序顺序中的第k个最大元素,而不是第k个不同元素.KthLargest类有一个构造方法,此构造方法有一个整数k和一个整数数组nums两个参数,它包含来自流的初始元素.对于方法KthLargest.add的每次调用,返回表示流中第k个最大元素的元素.例如: int k = 3; int [] arr = [4…

Kth Largest Element in an Array 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. Example 1: Input: [3,2,1,5,6,4] and k = 2 Output: 5 Example 2: Input: [3,2,3…

原题链接在这里:https://leetcode.com/problems/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. For example,Given [3,2,1,5,6,4] a…

636.Kth Largest Element in an Array 1.Problem 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. 题意很简单,找到一个一维数组中的第K大的数并返回.数组中第K大的数也是面试中经常考察的问题.现在就借Leetcode上的这题…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 方法一:移除最大值 方法二:排序 方法三:大顶堆 方法四:partition 日期 题目地址:https://leetcode.com/problems/kth-largest-element-in-an-array/description/ 题目描述 Find the kth largest element in an unsorted array…

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. For example, Given [3,2,1,5,6,4] and k = 2, return 5. Note: You may assume k is always valid, 1 ≤ k ≤ array'…

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. For example, Given [3,2,1,5,6,4] and k = 2, return 5. 解题思路: 本题是<算法导论>原题,9.2节用归并的思路给出了时间复杂度为O(n)的算法,9.3节给出了最…

examination questions 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. For example, Given [3,2,1,5,6,4] and k = 2, return 5. Note: You may assume k is always…

https://leetcode.com/problems/count-of-smaller-numbers-after-self/ You are given an integer array nums and you have to return a new counts array. The counts array has the property where counts[i] is the number of smaller elements to the right of nums…

leetcode面试准备:Kth Largest Element in an Array 1 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. For example, Given [3,2,1,5,6,4] and k = 2, return 5. Note…

版权声明: 本文为博主Bravo Yeung(知乎UserName同名)的原创文章,欲转载请先私信获博主允许,转载时请附上网址 http://blog.csdn.net/lzuacm. C#版 - Leetcode 215. Kth Largest Element in an Array-题解 在线提交: https://leetcode.com/problems/kth-largest-element-in-an-array/ Description Find the k th largest…

Design a class to find the kth largest element in a stream. Note that it is the kth largest element in the sorted order, not the kth distinct element. Your KthLargest class will have a constructor which accepts an integer k and an integer array nums,…

乘风破浪:LeetCode真题_034_Find First and Last Position of Element in Sorted Array 一.前言 这次我们还是要改造二分搜索,但是想法却有一点不一样. 二.Find First and Last Position of Element in Sorted Array 2.1 问题 2.2 分析与解决 查找问题,时间复杂度要求对数级别的,我们自然的想到了二分查找,和上一题一样,需求都是有点不一样的,这次是有重复的数字,找出某一特定的重…

乘风破浪:LeetCode真题_027_Remove Element 一.前言 这次是从数组中找到一个元素,然后移除该元素的所有结果,并且返回长度. 二.Remove Element 2.1 问题 2.2 分析与解决     这个题和上一题是非常相似的,只不过这次是从数组中找到给定的元素,并且删除该元素,同时返回剩余数组的长度,超过长度的元素不用管,存不存在都可以.于是我们想到了和上次一样的方法,用一个指针指向开始,一个指向结尾,开始的向后移动,如果遇到需要删除的元素,则用最后的元素替代,最后的…

Kth Largest Element in an Array 题解 题目来源:https://leetcode.com/problems/kth-largest-element-in-an-array/description/ Description Find the kth largest element in an unsorted array. Note that it is the kth largest element in the sorted order, not the kth…

lc 515 Find Largest Value in Each Tree Row 515 Find Largest Value in Each Tree Row You need to find the largest value in each row of a binary tree. Example: Input: 1 / \ 3 2 / \ \ 5 3 9 Output: [1, 3, 9] BFS Accepted 相比之前的几道用到BFS算法的题目,这题相对来说会繁琐一些,需要用…