原题链接在这里:https://leetcode.com/problems/minimum-score-triangulation-of-polygon/ 题目: Given N, consider a convex N-sided polygon with vertices labelled A[0], A[i], ..., A[N-1] in clockwise order. Suppose you triangulate the polygon into N-2 triangles.  F…

题目如下: Given N, consider a convex N-sided polygon with vertices labelled A[0], A[i], ..., A[N-1] in clockwise order. Suppose you triangulate the polygon into N-2 triangles.  For each triangle, the value of that triangle is the product of the labels of…

Given N, consider a convex N-sided polygon with vertices labelled A[0], A[i], ..., A[N-1] in clockwise order. Suppose you triangulate the polygon into N-2 triangles.  For each triangle, the value of that triangle is the product of the labels of the v…

https://leetcode.com/problems/minimum-score-triangulation-of-polygon/ 题意:给定一个凸的N边形(N<=50),每个顶点有一个权值A[i],把它分为N-2个三角形,每个三角形的val等于三个顶点的权值的乘积,问划分之后图形的val总和最小为多少. 一开始想到了,问题可以转换为求解子问题,由于没有想到如何进行状态转换,并且感觉贪心可行, 如下图1,将当前图形可以构成的三角形找出(红线为底边),从中找到val最小的三角形如图2,然后…

[LeetCode]Minimum Depth of Binary Tree Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. 递归和非递归,此提比较简单.广度优先遍历即可.关键之处就在于如何保持访问深度. 下面是4种代码: im…

Leetcode Find Minimum in Rotated Sorted Array 题目大意: 对一个有序数组翻转, 就是随机取前K个数,移动到数组的后面,然后让你找出最小的那个数.注意,K有可能是0,也就是没有翻转. 毫无疑问,遍历一次肯定能够找到,但这样时间复杂度是O(n).假设你在面试的时候遇到这种问题,你这样回答面试官肯定不会惬意的.我们接下来讨论有没有什么更快的方法.O(nlogn)?? 我还是把O(N)的代码贴出来,不知道为什么leetcode上竟然不超时. //O(n) c…

Leetcode 931. Minimum falling path sum 最小下降路径和(动态规划) 题目描述 已知一个正方形二维数组A,我们想找到一条最小下降路径的和 所谓下降路径是指,从一行到下一行,只能选择间距不超过1的列(也就是说第一行的第一列,只能选择第二行的第一列和第二列:第二行的第二列,只能选择第三行的第一列第二列第三列),最小下降路径就是这个路径的和最小 测试样例 Input: [[1,2,3],[4,5,6],[7,8,9]] Output: 12 Explanation:…

Given strings S and T, find the minimum (contiguous) substring W of S, so that T is a subsequenceof W. If there is no such window in S that covers all characters in T, return the empty string "". If there are multiple such minimum-length windows…

Follow up for "Find Minimum in Rotated Sorted Array":What if duplicates are allowed? Would this affect the run-time complexity? How and why? Suppose a sorted array is rotated at some pivot unknown to you beforehand. (i.e., 0 1 2 4 5 6 7 might be…

Suppose a sorted array is rotated at some pivot unknown to you beforehand. (i.e., 0 1 2 4 5 6 7 might become 4 5 6 7 0 1 2). Find the minimum element. You may assume no duplicate exists in the array. 这道寻找旋转有序数组的最小值肯定不能通过直接遍历整个数组来寻找,这个方法过于简单粗暴,这样的话,旋不…