我们把数组 A 中符合下列属性的任意连续子数组 B 称为 “山脉”: B.length >= 3 存在 0 < i < B.length - 1 使得 B[0] < B[1] < ... B[i-1] < B[i] > B[i+1] > ... > B[B.length - 1](注意:B 可以是 A 的任意子数组,包括整个数组 A.) 给出一个整数数组 A,返回最长 “山脉” 的长度. 如果不含有 “山脉” 则返回 0. 示例 1: 输入:[2,1,…

Let's call any (contiguous) subarray B (of A) a mountain if the following properties hold: B.length >= 3 There exists some 0 < i < B.length - 1 such that B[0] < B[1] < ... B[i-1] < B[i] > B[i+1] > ... > B[B.length - 1] (Note tha…

Let's call any (contiguous) subarray B (of A) a mountain if the following properties hold: B.length >= 3 There exists some 0 < i < B.length - 1 such that B[0] < B[1] < ... B[i-1] < B[i] > B[i+1] > ... > B[B.length - 1] (Note tha…

1. 题目 2. 解答 2.1 方法一 left 数组表示当前元素左边比当前元素小的元素个数,right 数组数组表示当前元素右边比当前元素小的元素个数.在山脉的中间 B[i] 处,其左边和右边肯定都有小于 B[i] 的元素,而山脉的长度即为 left[i] + right[i] + 1. class Solution { public: int longestMountain(vector<int>& A) { int n = A.size(); if (n < 3) retu…

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 双数组 参考资料 日期 题目地址:https://leetcode.com/problems/longest-mountain-in-array/description/ 题目描述 Let's call any (contiguous) subarray B (of A) a mountain if the following properties…

Given an unsorted array of integers, find the length of the longest consecutive elements sequence.For example,Given [100, 4, 200, 1, 3, 2],The longest consecutive elements sequence is [1, 2, 3, 4]. Return its length: 4.Your algorithm should run in O(…

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'…

Given an array of integers and an integer k, you need to find the number of unique k-diff pairs in the array. Here a k-diff pair is defined as an integer pair (i, j), where i and j are both numbers in the array and their absolute difference is k. Exa…

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: [3,2,3,1,2,4,5,5,6] and k = 4 Output:…

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: [3,2,3,1,2,4,5,5,6] and k = 4 Output:…