Ullas Kunder

Writing / 65 entries

Code, Solutions
& Discovery.

A public digital garden — bugs, breakthroughs, and the chaos of building things on the web.

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17
May 14, 2026#leetcode#python

LeetCode 54: Spiral Matrix

Peel the matrix layer by layer using four shrinking boundaries — a classic simulation problem.

18
May 13, 2026#leetcode#python

LeetCode 139: Word Break

A detailed breakdown of the DP string segmentation approach, optimizing for both speed and memory.

19
May 12, 2026#leetcode#python

LeetCode 98: Validate Binary Search Tree

Verify a BST's integrity by ensuring every node respects its upper and lower bounds during an inorder traversal.

20
May 11, 2026#leetcode#python

LeetCode 206: Reverse Linked List

Master both iterative and recursive approaches to reversing a singly linked list.

21
May 11, 2026#leetcode#python

LeetCode 62: Unique Paths

Master grid navigation by building intuition from 2D recursion to optimized 1D Dynamic Programming.

22
May 10, 2026#leetcode#python

LeetCode 152: Maximum Product Subarray

Track both maximum and minimum products to handle negative numbers in this DP problem.

23
May 9, 2026#leetcode#python

LeetCode 217: Contains Duplicate

Efficiently detect duplicates in an array using Hash Sets and Sorting.

24
May 9, 2026#leetcode#python

LeetCode 297: Serialize and Deserialize Binary Tree

Convert a binary tree into a string and back again using Preorder DFS.

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