Leetcode 2799. Count Complete Subarrays | Sliding Window + Hashmap | Python Explained Step-by-Step

In this video, we solve Leetcode 2799: "Count Complete Subarrays in an Array" using a clean and efficient sliding window + hashmap approach.

This is a great example of how to combine window-based traversal with frequency maps to count unique-element subarrays in Python.

✅ What you'll learn:

How to use sliding window to count subarrays
How to track frequency using defaultdict
Key Python tricks for interviews
Real-time dry run and full explanation

This video is beginner-friendly and perfect for Leetcode 2025 preparation, Python coding interviews, and those looking to master subarray counting logic.

📌 Problem: Count Complete Subarrays in an Array (Leetcode 2799)
📌 Level: Medium
📌 Technique: Sliding Window + HashMap
📌 Language: Python

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🔥 Tags
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