[CF865D]Buy Low Sell High(贪心) 题面 洛谷 CF 题解 首先有一个\(O(n^2)\)的\(dp\)很显然,设\(f[i][j]\)表示前\(i\)天手中还有\(j\)股股票的最大收益.转移显然. 然而这样子似乎并没有什么优化的余地. 考虑这样子一个贪心,假设我们已经知道了前面\(n-1\)天在最优答案的情况下的购买和卖出情况,只考虑最后这一天,那么你会找到一个可以买入股票的一天,并且其价格最小,然后和这一天的股票价格进行比较,如果更低,你就会在那一天买入股票,在这一…

题意:买卖股票,给你n个数,你可以选择买进或者卖出或者什么都不做,问你最后获得的最大收益是多少. Examples Input 910 5 4 7 9 12 6 2 10 Output 20 Input 203 1 4 1 5 9 2 6 5 3 5 8 9 7 9 3 2 3 8 4 Output 41In the first example, buy a share at 5, buy another at 4, sell one at 9 and another at 12. Then b…

https://vjudge.net/problem/CodeForces-867E 题意 一个物品在n天内有n种价格,每天仅能进行买入或卖出或不作为一种操作,可以同时拥有多种物品,问交易后的最大利益. 分析 贪心的取,当然是低买高卖.当买卖的顺序需要斟酌.考虑用小顶堆(优先队列)来维护这过程,我们每次得到一个新的价格,将其和堆顶的价格比较,如果比堆顶的价格低,就直接放入堆中,如果比堆顶的价格高,就意味着我们可以提前以堆顶的价格买入一个物品,然后以当前价格卖出,因此我们可以算出本次收益加到总收益…

/* 贪心来选择, 如果能找到比当前小的, 就用最小的来更新当前的 优先队列即可 */ #include<cstdio> #include<algorithm> #include<cstring> #include<queue> #include<iostream> #define ll long long #define mmp make_pair #define M using namespace std; int read() { int…

\(\\​\) \(Description\) 给出\(N\)天股票的价钱\(A_1,...,A_N\),每天可以什么都不做,或者买入或卖出\(1\)支股票,分别花出或收入\(A_i\)元,求最大收益. \(N\in [1,3\times10^5]\),\(A_i\in [1,10^6]\) \(\\\) \(Solution\) 贪心,显然每天的一支股票只有两种选择,这种情况下通常用堆去维护当前最优代价,问题是如何消去交换的影响. 具体地说,首先有一个简单的思路就是,按时间顺序将价格插入一个小…

Description 有nn个城市,第ii个城市商品价格为aiai​,从11城市出发依次经过这nn个城市到达n n城市,在每个城市可以把手头商品出售也可以至多买一个商品,问最大收益. Input 第一行一整数T T表示用例组数,每组用例首先输入一整数nn表示城市数量,之后输出nn个整数ai ai​表示每个城市商品单价 (1≤T≤250,1≤n≤105,∑n≤5⋅105) Output 输出最大收益 sol:显然是贪心题:不难证明下面的东西是对的. 如果某天的价格不能卖,那么插入队列一次,表示这…

正解:贪心 解题报告: 传送门! 这题首先有个很显然的dp,太基础了不说QAQ 然后考虑dp是n2的,显然过不去,所以换一个角度 然后发现这题和普通的dp的题有什么不同呢?就它这儿是一天只能买一支股,所以考虑怎么从这儿下手? 为了方便表示这里先define一下,x表示卖出价格,y表示买入价格 现在考虑如果是只考虑最后一天,那显然是从前面没买股票的日子中找到一天买股票的价格最低的,和最后一天股票的卖出价格做对比,如果能赚钱就卖,就欧克了 但是显然这样只能决定最后一天,因为显然可能存在当前来说今天卖…

大意: 第i天可以花$a_i$元买入或卖出一股或者什么也不干, 初始没钱, 求i天后最大收益 考虑贪心, 对于第$x$股, 如果$x$之前有比它便宜的, 就在之前的那一天买, 直接将$x$卖掉. 并不需要计算出最优的卖出时间, 因为若$x$后有更优价格, 可以再买回$x$, 不影响贪心结果 #include <iostream> #include <algorithm> #include <math.h> #include <cstdio> #include…

[题意]已知n天股价,每天可以买入一股或卖出一股或不作为,最后必须持0股,求最大收益. [算法]堆 贪心? [题解] 不作为思想:[不作为=买入再卖出] 根据不作为思想,可以推出中转站思想. 中转站思想:[买卖可以借助中转站,差值累加] 做法:从左到右,每次将两个-v加入堆,然后取大堆顶出来组成买卖. 理解:每个数字都和前面一个数字配对,然后在堆中留下两个数字,第一次访问表示转为中转站,第二次访问表示买该数字. 特别地,当前面没有比它小的数字时,会和自己组成买卖,就直接省去中转站功能. ★其实这…

<span style="font-family: Arial, Helvetica, sans-serif; background-color: rgb(255, 255, 255);">leetcode第188题,Best Time to Buy and Sell Stock IV题目如下:</span> https://leetcode.com/problems/best-time-to-buy-and-sell-stock-iv/ Say you hav…

Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete at most two transactions. Note:You may not engage in multiple transactions at the same time (ie,…

Best Time to Buy and Sell Stock Say you have an array for which the ith element is the price of a given stock on day i. If you were only permitted to complete at most one transaction (ie, buy one and sell one share of the stock), design an algorithm…

题目要求: 最多交易两次,并且只能买卖完之后再买. 总思路: 在数组中找一个适当的点i,使得i左右两边profit之和最大. 思路: 1.从左往右扫描,left[i]记录包括i元素以内的左部的maxprofit,用Best Time to Buy and Sell Stock 1可得到. 2.从右往左扫描,right[i]记录i+1到尾部元素的maxprofit,将上面的low改成big即可 3.返回max(left[i],right[i]) 注意: 1.考虑好,包括i与不包括i的情况 2.考虑…

Best Time to Buy and Sell Stock Say you have an array for which the ith element is the price of a given stock on day i. If you were only permitted to complete at most one transaction (ie, buy one and sell one share of the stock), design an algorithm…

本文是在学习中的总结,欢迎转载但请注明出处:http://blog.csdn.net/pistolove/article/details/43740415 Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete at most two transac…

Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete at most two transactions. Note: You may not engage in multiple transactions at the same time (i.e…

Best Time to Buy and Sell Stock I 题目: Say you have an array for which the ith element is the price of a given stock on day i. If you were only permitted to complete at most one transaction (ie, buy one and sell one share of the stock), design an algo…

Buy Low, Buy Lower The advice to "buy low" is half the formula to success in the stock market. But to be considered a great investor you must also follow this problems' advice: "Buy low, buy lower" That is, each time you buy a stock, y…

题目 Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete as many transactions as you like (ie, buy one and sell one share of the stock multiple times)…

Question: Best Time to Buy and Sell Stock Say you have an array for which the ith element is the price of a given stock on day i. If you were only permitted to complete at most one transaction (ie, buy one and sell one share of the stock), design an…

Best Time to Buy and Sell Stock 题解 原创文章,拒绝转载 题目来源:https://leetcode.com/problems/best-time-to-buy-and-sell-stock/description/ Description Say you have an array for which the ith element is the price of a given stock on day i. If you were only permitte…

[121-Best Time to Buy and Sell Stock(最佳买卖股票的时间)] [LeetCode-面试算法经典-Java实现][全部题目文件夹索引] 原题 Say you have an array for which the ith element is the price of a given stock on day i. If you were only permitted to complete at most one transaction (ie, buy on…

题目描述 Description The advice to "buy low" is half the formula to success in the bovine stock market.To be considered a great investor you must also follow this problems' advice: "Buy low; buy lower" Each time you buy a stock, you must p…

Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete as many transactions as you like (ie, buy one and sell one share of the stock multiple times) wit…

Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete at most k transactions. Note:You may not engage in multiple transactions at the same time (ie, yo…

Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete at most two transactions. Note:You may not engage in multiple transactions at the same time (ie,…

Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete as many transactions as you like (ie, buy one and sell one share of the stock multiple times). Ho…

Say you have an array for which the ith element is the price of a given stock on day i. If you were only permitted to complete at most one transaction (ie, buy one and sell one share of the stock), design an algorithm to find the maximum profit. 这道题相…

Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete as many transactions as you like (ie, buy one and sell one share of the stock multiple times). Ho…

Say you have an array for which the ith element is the price of a given stock on day i. If you were only permitted to complete at most one transaction (ie, buy one and sell one share of the stock), design an algorithm to find the maximum profit. Have…