Find All Anagrams Problem Statement

Given a string STR and a non-empty string PTR, identify all the starting indices of anagrams of PTR within STR.

Explanation:

An anagram of a string is another string that can be rearranged using exactly the same characters. For example, "SILENT" and "LISTEN" are anagrams, while "ABA" and "ABB" are not.

Input:

The first line contains an integer 'T', the number of test cases. Each test case includes: 
 - Two integers 'N' and 'M': the lengths of strings 'STR' and 'PTR' respectively. 
 - A string 'STR' of length 'N'. 
 - A string 'PTR' of length 'M'. 

Output:

For each test case, print the list of starting indices of all anagram substrings of 'PTR' within 'STR'. Each result should be on a new line. 

Example:

Consider STR = "BACDGABCDA" and PTR = "ABCD".

Output:

[0, 5, 6]

Constraints:

• 1 ≤ T ≤ 100
• 1 ≤ N ≤ 105
• 1 ≤ M ≤ N
• Time limit: 1 second

Note:

• Both strings STR and PTR contain only uppercase English letters.
• If there are no anagram substrings, return an empty list.
• If multiple anagrams exist, indices should be in ascending order.
• You are only required to implement the function and return the result; printing is managed elsewhere.