Substring Anagrams

Determine the number of substrings within a larger string that are anagrams of a given target string. This problem tests your ability to efficiently compare strings and identify patterns, crucial for tasks like data analysis and text processing.

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Problem Statement

Given a main string and a target string, both containing only lowercase English letters, your task is to find how many substrings within the main string are anagrams of the target string. An anagram is a rearrangement of letters, meaning two strings are anagrams if they contain the same characters with the same frequencies, regardless of order.

Example 1

Input: {'main_string': 'xyzyzyx', 'target_string': 'zyx'}

Output: 3

The substrings 'xyz', 'zyx', and 'yzy' are anagrams of 'zyx'.

Example 2

Input: {'main_string': 'abbcabc', 'target_string': 'abc'}

Output: 2

The substrings 'bca' and 'cab' are anagrams of 'abc'.

Constraints

-1 <= length of main_string <= 10^4
-1 <= length of target_string <= 10^4
-main_string and target_string contain only lowercase English letters.

Brute Force Approach

The brute force approach involves checking every possible substring of the main string to see if it's an anagram of the target string. Imagine you're comparing every possible handful of scrabble tiles from a big pile to your desired word. This means generating all substrings, comparing their lengths, and then comparing their character frequencies. The time complexity is high because of the nested loops required to generate and compare substrings.

TimeO(m*n*k)

SpaceO(1)

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