Notes and solution for LeetCode problems (Top Interview 150) by William Wong.
The problems are split into the following topics:
| Topic | Done |
|---|---|
| Array / Strings | 13/24 |
| Two Pointers | |
| Sliding Window | |
| Matrix | |
| Hashmap | |
| Intervals | |
| Stack | |
| Linked List | |
| Binary Tree General | |
| Binary Tree BFS | |
| Binary Search Tree | |
| Graph General | |
| Graph BFS | |
| Trie | |
| Backtracking | |
| Divide & Conquer | |
| Kadane's Algorithm | |
| Binary Search | |
| Heap | |
| Bit Manipulation | |
| Math | |
| 1D DP | |
| Multidim. DP |
In my blog, I offer a summary of the thought process and code (usually in Java, Python or C++) for each solved problem.
In LeetCode, the tasks often require you to modify an array of size n in-place. In some cases, the modified array will have a size smaller than n (e.g. removing certain elements). The tester verifies the array based on the returned parameter k, which denotes the number of the first k-elements which are suppossed to be "correct" according to the task. Make sure k is correct! Depending on the task description which can be quite ambigious, you should return either 1) number of elements or 2) index of the last element.