P18472 [CodeChef] MAXTHEMIN
普及-
题目描述

JJ has an array A of size N. He can perform the following operations on the array at most K times:

Set A_{i} := A_{i + 1} where 1 ≤ i ≤ N - 1
Set A_{i} := A_{i - 1} where 2 ≤ i ≤ N

He wants to maximize the value of the minimum element of the array A. Formally, he wants to maximize the value of $\min\limits_{1$ ≤ i ≤ N} A_{i}.

Can you help him do so?

------ Input Format ------

  • The first line contains a single integer T - the number of test cases. Then the test cases follow.
  • The first line of each test case contains two integers N and K - the size of the array A and the maximum number of operations allowed respectively.
  • The second line of each test case contains $N space-separated integers A_{1}, A_{2}, \dots, A_{N}$ denoting the array A.

------ Output Format ------

For each test case, output the maximum value of the minimum element of the array A that can be obtained after applying the given operation at most K times.

------ Constraints ------

$1 ≤ T ≤ 100$
$2 ≤ N ≤ 10^{5}$
$0 ≤K ≤10^{5}$
$1 ≤A_{i} ≤10^{9}$
- Sum of $N$ over all test cases does not exceed $2 \cdot 10^{5}$

----- Sample Input 1 ------
4
5 4
5 4 3 2 1
6 1
8 2 3 9 6 10
5 2
4 3 4 3 5
5 1000
4 3 4 3 5

----- Sample Output 1 ------
5
3
4
5

----- explanation 1 ------
Test Case 1: We can perform the following operations (in the following order):
- Set $A_{2} := A_{1}$. Array $A$ becomes $[5, 5, 3, 2, 1]$
- Set $A_{3} := A_{2}$. Array $A$ becomes $[5, 5, 5, 2, 1]$
- Set $A_{4} := A_{3}$. Array $A$ becomes $[5, 5, 5, 5, 1]$
- Set $A_{5} := A_{4}$. Array $A$ becomes $[5, 5, 5, 5, 5]$

Therefore the answer is $5$.

Test Case 2: We can perform the following operations (in the following order):
- Set $A_{2} := A_{3}$. Array $A$ becomes $[8, 3, 3, 9, 6, 10]$

Therefore the answer is $3$.

Test Case 3: We can perform the following operations (in the following order):
- Set $A_{2} := A_{3}$. Array $A$ becomes $[4, 4, 4, 3, 5]$
- Set $A_{4} := A_{3}$. Array $A$ becomes $[4, 4, 4, 4, 5]$

Therefore the answer is $4$.

输入格式

见题面

输出格式

见题面

样例输入
4 5 4 5 4 3 2 1 6 1 8 2 3 9 6 10 5 2 4 3 4 3 5 5 1000 4 3 4 3 5
样例输出
5 3 4 5