Скачать или смотреть LeetCode 1254 | Number of Closed Islands | Python DFS Flood-Fill Explained | AlgoYogi

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In this video, we solve *LeetCode 1254: Number of Closed Islands* using Python and a clean *DFS flood-fill* approach. A closed island is a connected region of land (`0`) that is entirely surrounded by water (`1`) and does **not touch the grid boundary**.

👉 Problem Link: https://leetcode.com/problems/number-...

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​ Timestamps
0:00 Introduction
0:20 Problem Statement
1:10 DFS Flood-Fill Approach
9:00 Python Code Walkthrough
16:45 Time & Space Complexity

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Why Watch?
Learn how to use *DFS to flood-fill and mark visited land*
Invalidate islands touching the boundary first for clarity and efficiency :contentReference[oaicite:1]{index=1}
Simple O(m·n) solution ideal for matrix connectivity problems :contentReference[oaicite:2]{index=2}

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📢 Next Steps:
Practice related DFS/BFS grid problems on [AlgoYogi.io](https://algoyogi.io)
Share your Union-Find variant or tricky edge cases in the comments!

#LeetCode #ClosedIslands #DFS #Python #AlgoYogi #GridTraversal