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Posts Tagged: leetcode (Page 5)

Remove-all-adjacent-duplicates-in-string-ii Solution
You are given a string s and an integer k, a k duplicate removal consists of choosing k adjacent and equal letters from s and removing them, causing the left and the right side of the deleted substring to concatenate together...

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Lowest Common Ancestor of a Binary Tree
Questions involving the binary tree data structure are very popular in tech interviews, and can be challenging and varied! A binary tree is a data structure consisting of a collection of nodes (starting at a root node), where each node consists of a value (data), together with a directed edges to at most two nodes (the "left child" and "right child"), with the additional conditions that no two edges point to the same node and no edge points to the root. I recently solved an interesting problem on binary tree...

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Coin Change solution leetcode
It's one of the most popular questions on leetcode that seems very easy at first. Coin change is a classic dynamic programming problem. I will proceed with an obvious (albeit wrong) solution and subsequently proceed to an efficient correct solution...

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