POJ 1742 Coins( 单调队列优化多重背包)

本文介绍了一个关于多重背包的问题,Tony 想用不同面值的硬币购买手表,目标是找出所有可以用硬币组合成的不超过 m 的钱数。问题通过单调队列进行优化,避免了常规方法的超时问题。单调队列的原理是用于减少重复计算,通过对每个物品的容量分类,维护一个队列来保存合法的dp状态。

摘要生成于 C知道 ,由 DeepSeek-R1 满血版支持, 前往体验 >

Description
People in Silverland use coins.They have coins of value A1,A2,A3…An Silverland dollar.One day Tony opened his money-box and found there were some coins.He decided to buy a very nice watch in a nearby shop. He wanted to pay the exact price(without change) and he known the price would not more than m.But he didn’t know the exact price of the watch.
You are to write a program which reads n,m,A1,A2,A3…An and C1,C2,C3…Cn corresponding to the number of Tony’s coins of value A1,A2,A3…An then calculate how many prices(form 1 to m) Tony can pay use these coins.
Input
The input contains several test cases. The first line of each test case contains two integers n(1<=n<=100),m(m<=100000).The second line contains 2n integers, denoting A1,A2,A3…An,C1,C2,C3…Cn (1<=Ai<=100000,1<=Ci<=1000). The last test case is followed by two zeros.
Output
For each test case output the answer on a single line.
Sample Input
3 10
1 2 4 2 1 1
2 5
1 4 2 1
0 0
Sample Output
8
4

题意:

tony有n中硬币想去买一个手表面值分别为A1,A2,An个数分别为C1,C2,Cn。知道手表价格可能的最大值m,但不知道准确值,Tony不喜欢找零。问他的钱能组合出多少种(不超过m)的钱数。

tip:

可行性的多重背包问题,但是正常写法会超时。。所以采用单调队列优化,优化的原理就是当我么的值是1时,转化成为一个01背包,当这个num*v大于总体的m时,很显然是个完全背包,理由是,可以无限的取,直到你背包塞不下为止,剩下的可能,就是多重背包了,

http://blog.youkuaiyun.com/flyinghearts/article/details/5898183

讲解多重背包很好的文章QAQ

针对这道题。。。要的不是最大值,而是

评论
添加红包

请填写红包祝福语或标题

红包个数最小为10个

红包金额最低5元

当前余额3.43前往充值 >
需支付:10.00
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明:

1.余额是钱包充值的虚拟货币,按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载,可以购买VIP、付费专栏及课程。

余额充值