We have a string of length n, which consist only UPPER and LOWER CASE characters and we have a number k (always less than n and greater than 0). We can make at most k changes in our string such that we can get a sub-string of maximum length which have all same characters.
The first line of the input contains an integer T which denotes the number of test cases to follow. Each test case contains space separated 2 integers n and k. Next line has a string of length n.
Print an integer which denotes the maximum length possible.