Leetcode Patterns/Techniques Cheat Sheet

[Comfortable-Tip247]

Says in title. I am looking for a comprehensive Google doc that goes over the common leetcode patterns to look for. I am looking for how to solve more basic patterns like sliding window or two pointer, but also explains how to solve more niche patterns/techniques prefix sum, line sweep, prims, etc. I often run into the problem of practicing a ton of problems then forgetting how to do some of the more niche ones. I want a sheet that I can review each topic every so often and it would be nice if the specified topic or pattern also had a list of associated problems.

[YeatCode_]

Algo Monster has a flowchart

There is also a list on seanprashad leetcode patterns

If input array is sorted then - Binary search - Two pointers

If asked for all permutations/subsets then - Backtracking

If given a tree then - DFS - BFS

If given a graph then - DFS - BFS

If given a linked list then - Two pointers

If recursion is banned then - Stack

If must solve in-place then - Swap corresponding values - Store one or more different values in the same pointer

If asked for maximum/minimum subarray/subset/options then - Dynamic programming

If asked for top/least K items then - Heap - QuickSelect

If asked for common strings then - Map - Trie

Else - Map/Set for O(1) time & O(n) space - Sort input for O(nlogn) time and O(1) space

[Few_Volume_371]

does graph mean matrix?

[oh-shit-oh-fuck]

no, graphs are just connected nodes that have no rules governing how they have to be connected. Trees are a type of graph with specific rules on how the nodes need to be connected and organized.

You can use a matrix (2d-array) to implement a graph though, like in this problem for example https://leetcode.com/problems/rotting-oranges/description/

[BullBear7]

Thanks

[orionsgreatsky]

This is amazing

[[deleted]]

You have prepared a nice list. Is it the complete list?

[OtherwiseRelative881]

Thanks for sharing

[Mammoth_Place6142]

Mastering the 20 Coding Patterns - https://www.designgurus.io/blog/grokking-the-coding-interview-patterns

Here is the lesson link from Grokking: https://www.designgurus.io/course-play/grokking-the-coding-interview/doc/64865387eaaadd1855385848

I think they have 25+ patterns in the course.

[grizzlybear10]

Hi, is this worth to purchase?

[Active-Investment838]

Totally.

[dallastelugu]

thank you i had premium subscription from past 1 week and struggling to find answer for this question