Anagram Substring Search

Given two strings 'STR' and 'PTR', identify all starting indices of 'PTR' anagram substrings in 'STR'. Two strings are anagrams if one can be rearranged to form the other.

Input:

First line: Integer T (number of test cases).
Each test case consists of:
Line 1: Two integers N and M.
Line 2: String 'STR' with N characters.
Line 3: String 'PTR' with M characters.

Output:

For each test case, output the list of starting indices of 'PTR' anagram substrings in 'STR', each consecutive list on a new line.

Example:

Input:

1
9 4
BACDGABCD
ABCD

Output:

0 5

Explanation:

The substrings at indices 0-3 ('BACD') and 5-8 ('ABCD') in 'STR' are anagrams of 'PTR'.

Constraints:

• 1 ≤ T ≤ 50
• 1 ≤ N, M ≤ 10⁴
• Strings consist of only uppercase English letters.

Note:

No need to print anything in the function; return the answer.