Permutation in String | Brute Force + Sliding Window (Frequency Map) | Python, C++, Java
In this video, we solve the popular Permutation in String problem from LeetCode.
We first understand the brute force approach by checking all substrings and then move to the optimized sliding window solution using frequency maps.
You will learn:
How to identify if a permutation of one string exists in another
Brute force approach and its limitations
Sliding window technique with fixed window size
Using frequency array / hashmap to match characters
Difference between one map vs two map approach
How to efficiently compare frequencies
Time complexity optimization from O(n * k) to O(n)
Clean and interview-ready code in Python, C++, and Java
This problem is very important for mastering sliding window with fixed size and is frequently asked in coding interviews.
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