B'Word s of length n is called k -complete if For example, "abaaba" is a 3 -complete word, while "abccba" is not. Bob is given a word s of length n consisting of only lowercase Latin letters and an integer k , such that n is divisible by k . He wants to convert s to any k -complete word. To do this Bob can choose some i ( 1 <= i <= n ) and replace the letter at position i with some other lowercase Latin letter. So now Bob wants to know the minimum number of letters he has to replace to convert s to any k -complete word. Note that Bob can do zero changes if the word s is already k -complete. You are required to answer t test cases independently. The first line contains a single integer t ( 1 <= t <= 10^5 ) -- the number of test cases. The first line of each test case contains two integers n and k ( 1 <= k < n <= 2 cdot 10^5 , n is divisible by k ). The second line of each test case contains a word s of length n . It is guaranteed that word s only contains lowercase Latin letters. And it is guaranteed that the sum of n over all test cases will not exceed 2 cdot 10^5 . For each test case, output one integer, representing the minimum number of characters he has to replace to convert s to any k -complete word. In the first test case, one optimal solution is aaaaaa. In the second test case, the given word itself is k -complete. '...