XueWang1的博客

地址：https://leetcode.com/problems/binary-tree-maximum-path-sum/Given anon-emptybinary tree, find the maximum path sum.For this problem, a path is defined as any sequence of nodes from some starti...

leetcode原题地址：https://leetcode.com/problems/best-time-to-buy-and-sell-stock-iv/REFERENCE:https://leetcode.com/problems/best-time-to-buy-and-sell-stock-iii/discuss/135704/Detail-explanation-of-DP-so...

原题地址：https://leetcode.com/problems/coin-change/这个题目可以用dfs来写，但是很容易超时，需要剪枝。dp中有经典的背包九讲，而此题目正好是一种完全背包的模型。首先看完全背包模型：有 N 种物品和一个容量为 V 的背包，每种物品都有无限件可用。放入第 i 种物品 的费用是 Ci，价值是 Wi。求解：将哪些物品装入背包，可使这些物品的耗费的...

https://leetcode-cn.com/contest/biweekly-contest-7/problems/optimize-water-distribution-in-a-village/这个题目可以转化为最小生成树。构建虚拟结点0，并且将所有结点与之联系，长度为wi，如下：然后对改图求最小生成树，即可求得最小cost。struct Edge{ int ...

https://leetcode.com/problems/minimum-cost-to-connect-sticks/思路，将两个短的求和，然后放入数列中；再取两个短的；因此是霍夫曼树。使用优先级队列即可：class Solution {public: int connectSticks(vector<int>& sticks) { ...