#D12661. Electrification
Electrification
Electrification
At first, there was a legend related to the name of the problem, but now it's just a formal statement.
You are given n points a_1, a_2, ..., a_n on the OX axis. Now you are asked to find such an integer point x on OX axis that f_k(x) is minimal possible.
The function f_k(x) can be described in the following way:
- form a list of distances d_1, d_2, ..., d_n where d_i = |a_i - x| (distance between a_i and x);
- sort list d in non-descending order;
- take d_{k + 1} as a result.
If there are multiple optimal answers you can print any of them.
Input
The first line contains single integer T ( 1 ≤ T ≤ 2 ⋅ 10^5) — number of queries. Next 2 ⋅ T lines contain descriptions of queries. All queries are independent.
The first line of each query contains two integers n, k (1 ≤ n ≤ 2 ⋅ 10^5, 0 ≤ k < n) — the number of points and constant k.
The second line contains n integers a_1, a_2, ..., a_n (1 ≤ a_1 < a_2 < ... < a_n ≤ 10^9) — points in ascending order.
It's guaranteed that ∑{n} doesn't exceed 2 ⋅ 10^5.
Output
Print T integers — corresponding points x which have minimal possible value of f_k(x). If there are multiple answers you can print any of them.
Example
Input
3 3 2 1 2 5 2 1 1 1000000000 1 0 4
Output
3 500000000 4
inputFormat
Input
The first line contains single integer T ( 1 ≤ T ≤ 2 ⋅ 10^5) — number of queries. Next 2 ⋅ T lines contain descriptions of queries. All queries are independent.
The first line of each query contains two integers n, k (1 ≤ n ≤ 2 ⋅ 10^5, 0 ≤ k < n) — the number of points and constant k.
The second line contains n integers a_1, a_2, ..., a_n (1 ≤ a_1 < a_2 < ... < a_n ≤ 10^9) — points in ascending order.
It's guaranteed that ∑{n} doesn't exceed 2 ⋅ 10^5.
outputFormat
Output
Print T integers — corresponding points x which have minimal possible value of f_k(x). If there are multiple answers you can print any of them.
Example
Input
3 3 2 1 2 5 2 1 1 1000000000 1 0 4
Output
3 500000000 4
样例
3
3 2
1 2 5
2 1
1 1000000000
1 0
4
3
500000000
4
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