Update README.md

Author: kamyu104

README.md

@@ -848,7 +848,7 @@
 2812 | [Find the Safest Path in a Grid](https://leetcode.com/problems/find-the-safest-path-in-a-grid/)  | [C++](./C++/find-the-safest-path-in-a-grid.cpp) [Python](./Python/find-the-safest-path-in-a-grid.py) | _O(n^2)_ | _O(n^2)_| Medium           || BFS, Bucket Sort, Union Find, `Dijkstra's Algorithm`, Binary Search | 
 2814 | [Minimum Time Takes to Reach Destination Without Drowning](https://leetcode.com/problems/minimum-time-takes-to-reach-destination-without-drowning/)  | [C++](./C++/minimum-time-takes-to-reach-destination-without-drowning.cpp) [Python](./Python/minimum-time-takes-to-reach-destination-without-drowning.py) | _O(m * n)_ | _O(m * n)_| Hard           | 🔒 | Simulation, BFS | 
 2852 | [Sum of Remoteness of All Cells](https://leetcode.com/problems/sum-of-remoteness-of-all-cells/)| [C++](./C++/sum-of-remoteness-of-all-cells.cpp) [Python](./Python/sum-of-remoteness-of-all-cells.py)| _O(n^2)_ | _O(n^2)_ | Medium | 🔒 | Flood Fill, BFS, Math |
-3157 | [Find the Level of Tree with Minimum Sum](https://leetcode.com/problems/find-the-level-of-tree-with-minimum-sum/)| [C++](./C++/find-the-level-of-tree-with-minimum-sum.cpp) [Python](./Python/find-the-level-of-tree-with-minimum-sum.py)| _O(n)_ | _O(n)_ | Medium | 🔒 | BFS |
+3157 | [Find the Level of Tree with Minimum Sum](https://leetcode.com/problems/find-the-level-of-tree-with-minimum-sum/)| [C++](./C++/find-the-level-of-tree-with-minimum-sum.cpp) [Python](./Python/find-the-level-of-tree-with-minimum-sum.py)| _O(n)_ | _O(w)_ | Medium | 🔒 | BFS |
 
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