CF1557B Moamen and k-subarrays
Description
Moamen has an array of $ n $ distinct integers. He wants to sort that array in non-decreasing order by doing the following operations in order exactly once:
1. Split the array into exactly $ k $ non-empty subarrays such that each element belongs to exactly one subarray.
2. Reorder these subarrays arbitrary.
3. Merge the subarrays in their new order.
A sequence $ a $ is a subarray of a sequence $ b $ if $ a $ can be obtained from $ b $ by deletion of several (possibly, zero or all) elements from the beginning and several (possibly, zero or all) elements from the end.
Can you tell Moamen if there is a way to sort the array in non-decreasing order using the operations written above?
Input Format
The first line contains a single integer $ t $ ( $ 1 \le t \le 10^3 $ ) — the number of test cases. The description of the test cases follows.
The first line of each test case contains two integers $ n $ and $ k $ ( $ 1 \le k \le n \le 10^5 $ ).
The second line contains $ n $ integers $ a_1, a_2, \ldots, a_n $ ( $ 0 \le |a_i| \le 10^9 $ ). It is guaranteed that all numbers are distinct.
It is guaranteed that the sum of $ n $ over all test cases does not exceed $ 3\cdot10^5 $ .
Output Format
For each test case, you should output a single string.
If Moamen can sort the array in non-decreasing order, output "YES" (without quotes). Otherwise, output "NO" (without quotes).
You can print each letter of "YES" and "NO" in any case (upper or lower).
Explanation/Hint
In the first test case, $ a = [6, 3, 4, 2, 1] $ , and $ k = 4 $ , so we can do the operations as follows:
1. Split $ a $ into $ \{ [6], [3, 4], [2], [1] \} $ .
2. Reorder them: $ \{ [1], [2], [3,4], [6] \} $ .
3. Merge them: $ [1, 2, 3, 4, 6] $ , so now the array is sorted.
In the second test case, there is no way to sort the array by splitting it into only $ 2 $ subarrays.
As an example, if we split it into $ \{ [1, -4], [0, -2] \} $ , we can reorder them into $ \{ [1, -4], [0, -2] \} $ or $ \{ [0, -2], [1, -4] \} $ . However, after merging the subarrays, it is impossible to get a sorted array.