HDU 6197 array array array(最长不下降子序列)

桃扇骨 2022-06-08 01:17 200阅读 0赞

# array array array #

**Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)  
Total Submission(s): 0 Accepted Submission(s): 0**

Problem Description

One day, Kaitou Kiddo had stolen a priceless diamond ring. But detective Conan blocked Kiddo's path to escape from the museum. But Kiddo didn't want to give it back. So, Kiddo asked Conan a question. If Conan could give a right answer, Kiddo would return the ring to the museum.  
Kiddo: "I have an array  A and a number  k, if you can choose exactly  k elements from  A and erase them, then the remaining array is in non-increasing order or non-decreasing order, we say  A is a magic array. Now I want you to tell me whether  A is a magic array. " Conan: "emmmmm..." Now, Conan seems to be in trouble, can you help him?

Input

The first line contains an integer T indicating the total number of test cases. Each test case starts with two integers  n and  k in one line, then one line with  n integers:  A1,A2…An.  
 1≤T≤20  
 1≤n≤105  
 0≤k≤n  
 1≤Ai≤105

Output

For each test case, please output "A is a magic array." if it is a magic array. Otherwise, output "A is not a magic array." (without quotes).

Sample Input

3
    4 1
    1 4 3 7
    5 2
    4 1 3 1 2
    6 1
    1 4 3 5 4 6

Sample Output

A is a magic array.
    A is a magic array.
    A is not a magic array.

Source

[2017 ACM/ICPC Asia Regional Shenyang Online][2017 ACM_ICPC Asia Regional Shenyang Online]

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liuyiding

题解：  
这是比赛我做出的第一题。。比较简单，直接正着和反着求一遍最长不下降子序列，然后把总长减去序列长度和k比较一下就行了  
然后一开始我tle了。。。后来改成nlogn的做法就ac了  
代码没有了。。。hdu不允许提出来我的忘记存了

[2017 ACM_ICPC Asia Regional Shenyang Online]: http://acm.hdu.edu.cn/search.php?field=problem&key=2017+ACM%2FICPC+Asia+Regional+Shenyang+Online&source=1&searchmode=source