Unique Substrings Counter

You are given a string S and an integer K. Your task is to count the number of unique substrings of length \(K\) in S. A substring is a contiguous sequence of characters extracted from S. If \(K\) is greater than the length of S, then the answer is 0.

For example, if S = "abacab" and K = 3, the unique substrings are "aba", "bac", "aca", and "cab", so the output is 4.

Read the input from standard input (stdin) and output the answer for each test case on a new line to standard output (stdout).

inputFormat

The first line of input contains an integer T, the number of test cases. Each of the next T lines contains a string S and an integer K separated by a space.

outputFormat

For each test case, output a single line containing the number of unique substrings of length K in the string S.## sample

2
abacab 3
abcdef 2

4
5