A. Heidi and Library (easy)
time limit per test

2 seconds

memory limit per test

256 megabytes

input

standard input

output

standard output

Your search for Heidi is over – you finally found her at a library, dressed up as a human. In fact, she has spent so much time there that she now runs the place! Her job is to buy books and keep them at the library so that people can borrow and read them. There are n different books, numbered 1 through n.

We will look at the library's operation during n consecutive days. Heidi knows in advance that on the i-th day (1 ≤ i ≤ n) precisely one person will come to the library, request to borrow the book ai, read it in a few hours, and return the book later on the same day.

Heidi desperately wants to please all her guests, so she will make sure to always have the book ai available in the library on the i-th day. During the night before the i-th day, she has the option of going to the bookstore (which operates at nights to avoid competition with the library) and buying any book for the price of 1 CHF. Of course, if she already has a book at the library, she does not need to buy it again. Initially, the library contains no books.

There is a problem, though. The capacity of the library is k – this means that at any time, there can be at most k books at the library. If buying a new book would cause Heidi to have more than k books, she must first get rid of some book that she already has, in order to make room for the new book. If she later needs a book that she got rid of, she will need to buy that book again.

You are given k and the sequence of requests for books a1, a2, ..., an. What is the minimum cost (in CHF) of buying new books to satisfy all the requests?

Input

The first line of input will contain two integers n and k (1 ≤ n, k ≤ 80). The second line will contain n integers a1, a2, ..., an(1 ≤ ai ≤ n) – the sequence of book requests.

Output

On a single line print the minimum cost of buying books at the store so as to satisfy all requests.

Examples
input
4 80
1 2 2 1
output
2
input
4 1
1 2 2 1
output
3
input
4 2
1 2 3 1
output
3
Note

In the first test case, Heidi is able to keep all books forever. Therefore, she only needs to buy the book 1 before the first day and the book2 before the second day.

In the second test case, she can only keep one book at a time. Therefore she will need to buy new books on the first, second and fourth day.

In the third test case, before buying book 3 on the third day, she must decide which of the books 1 and 2 she should get rid of. Of course, she should keep the book 1, which will be requested on the fourth day.

#include<iostream>
#include<cstdio>
#include<cmath>
#include<cstring>
#include<sstream>
#include<algorithm>
#include<queue>
#include<deque>
#include<iomanip>
#include<vector>
#include<cmath>
#include<map>
#include<stack>
#include<set>
#include<fstream>
#include<memory>
#include<list>
#include<string>
using namespace std;
typedef long long LL;
typedef unsigned long long ULL;
#define MAXN 88
#define MOD 1000000
#define INF 1000000009
#define eps 0.00000001
/*
贪心策略错误!每次需要去掉元素的时候,不是去掉以后出现次数最多的元素,
去掉下一次出现位置最晚的元素!这个元素占用图书馆空间的时间最长!
*/
int cnt[MAXN], a[MAXN], pos[MAXN];
int n, k;
int main()
{
scanf("%d%d", &n, &k);
for (int i = ; i < n; i++)
{
scanf("%d", &a[i]);
}
set<int> s;
int tmp = ;
for (int i = ; i < n; i++)
{
if (!s.count(a[i]))
{
if (s.size() == k)
{
int Max = -INF, p = -;
for (auto it = s.begin(); it != s.end(); it++)
{
int j;
for (j = i; j < n; j++)
{
if (a[j] == *it)
{
break;
}
}
if (j > Max)
{
Max = j;
p = *it;
}
}
s.erase(p);
//cout << "::::::::::::::" << p << endl;
}
s.insert(a[i]);
tmp++;
}
}
printf("%d\n", tmp);
}

贪心算法 Heidi and Library (easy)的更多相关文章

  1. 【贪心】codeforces A. Heidi and Library (easy)

    http://codeforces.com/contest/802/problem/A [题意] 有一个图书馆,刚开始没有书,最多可容纳k本书:有n天,每天会有人借一本书,当天归还:如果图书馆有这个本 ...

  2. C. Heidi and Library (神奇的网络流)

    C. Heidi and Library 题意 有 n 种分别具有价格 b 的书 a ,图书馆里最多同时存放 k 本书,已知接下来 n 天每天都有一个人来看某一本书,如果图书馆里没有则需要购买,问最少 ...

  3. 1033. To Fill or Not to Fill (25) -贪心算法

    题目如下: With highways available, driving a car from Hangzhou to any other city is easy. But since the ...

  4. 【CF802C】Heidi and Library(网络流)

    [CF802C]Heidi and Library(网络流) 题面 CF 洛谷 题解 前面两个Easy和Medium都是什么鬼玩意啊.... 不难发现如果这天的要求就是第\(a_i\)种书的话,那么\ ...

  5. CF802C Heidi and Library hard 费用流 区间k覆盖问题

    LINK:Heidi and Library 先说一下简单版本的 就是权值都为1. 一直无脑加书 然后发现会引起冲突,可以发现此时需要扔掉一本书. 扔掉的话 可以考虑扔掉哪一本是最优的 可以发现扔掉n ...

  6. 题解-CF802C Heidi and Library (hard)

    题面 CF802C Heidi and Library (hard) 有一个大小为 \(k\) 的空书架.有 \(n\) 天和 \(n\) 种书,每天要求书架中有书 \(a_i\).每天可以多次买书, ...

  7. LeetCode解题记录(贪心算法)(一)

    1. 前言 目前得到一本不错的算法书籍,页数不多,挺符合我的需要,于是正好借这个机会来好好的系统的刷一下算法题,一来呢,是可以给部分同学提供解题思路,和一些自己的思考,二来呢,我也可以在需要复习的时候 ...

  8. 贪心算法(Greedy Algorithm)

    参考: 五大常用算法之三:贪心算法 算法系列:贪心算法 贪心算法详解 从零开始学贪心算法 一.基本概念: 所谓贪心算法是指,在对问题求解时,总是做出在当前看来是最好的选择.也就是说,不从整体最优上加以 ...

  9. 算法导论----贪心算法,删除k个数,使剩下的数字最小

    先贴问题: 1个n位正整数a,删去其中的k位,得到一个新的正整数b,设计一个贪心算法,对给定的a和k得到最小的b: 一.我的想法:先看例子:a=5476579228:去掉4位,则位数n=10,k=4, ...

随机推荐

  1. A. Power Consumption Calculation

    http://codeforces.com/problemset/problem/10/A 题很简单,就是题意难懂啊... #include <stdio.h> #include < ...

  2. Parlay Wagering

    http://acm.sdut.edu.cn/sdutoj/problem.php?action=showproblem&problemid=2833 题意:讲述了一种投小钱赢大钱的赌博方式, ...

  3. App设计师常用的10大网页和工具大盘点

    1.Adobe Photoshop 老牌的设计工具,不用解释 2.Adobe Illustrator 同上,不解释 3.Balsamiq Mockup 网址:http://balsamiq.com/ ...

  4. Linux搭建tomcat文件服务器

    Linux搭建tomcat文件服务器 Linux下配置Tomcat服务器和Windows下其实差不多,可以去官网下载安装包释放或者在线下载,只是当时下载的windows.zip文件,现在下载.tar. ...

  5. Dockerfile镜像的制作

    Dockerfile镜像的制作 如果学习Docker,那么制作镜像这一步肯定不能少的,别人给你的是环境,而你自己做的才是你最终需要的东西,接下来就记录一下如何制作一个满足自己的镜像,我们使用docke ...

  6. 51nod1446 Kirchhoff矩阵+Gauss消元+容斥+折半DFS

    思路: //By SiriusRen #include <cstdio> #include <cstring> #include <algorithm> using ...

  7. 【洛谷3224/BZOJ2733】[HNOI2012]永无乡 (Splay启发式合并)

    题目: 洛谷3224 分析: 这题一看\(n\leq100000\)的范围就知道可以暴力地用\(O(nlogn)\)数据结构乱搞啊-- 每个联通块建一棵Splay树,查询就是Splay查询第k大的模板 ...

  8. zoj3675 BFS+状态压缩

    #include <stdio.h> #include <string.h> #include <queue> using namespace std; int n ...

  9. ACM_Alien And Password

    Alien And Password Time Limit: 2000/1000ms (Java/Others) Problem Description: Alien Fred wants to de ...

  10. 354 Russian Doll Envelopes 俄罗斯娃娃信封

    You have a number of envelopes with widths and heights given as a pair of integers (w, h). One envel ...