Top 5 Most Common Graph Algorithms for Coding Interviews

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⭐ BLIND-75 PLAYLIST: • Two Sum - Leetcode 1 -...
💡 CODING SOLUTIONS: • Coding Interview Solut...
💡 DYNAMIC PROGRAMMING PLAYLIST: • House Robber - Leetco...
🌲 TREE PLAYLIST: • Invert Binary Tree - D...
💡 GRAPH PLAYLIST: • Course Schedule - Grap...
💡 BACKTRACKING PLAYLIST: • Word Search - Backtrac...
💡 LINKED LIST PLAYLIST: • Reverse Linked List - ...
💡 BINARY SEARCH PLAYLIST: • Binary Search
Union-Find Solution - • Number of Connected Co...
Topological Sort Solution - • Alien Dictionary - Top...
Dijkstra's Solution - • Network Delay Time - D...
0:00 - Intro
0:10 - 1. DFS
2:40 - 2. BFS
4:55 - 3. Union-Find
6:45 - 4. Topological Sort
8:47 - 5. Dijkstra's Algo
12:00 - Extra Graph Algorithms
#common #graph #algorithm
Disclosure: Some of the links above may be affiliate links, from which I may earn a small commission.

[@NeetCode]

🚀 neetcode.io/ - I created a FREE site to make interview prep a lot easier, hope it helps! ❤

[@DennisWanyonyi]

Unfortunately VMv4 doesn't work when redeemed as a coupon

[@eyekenspel1765]

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[@eyekenspel1765]

@@DennisWanyonyi q+qqqqqq++++q+qqq+q+qq+++qqqqqq1q++q+qqqqq+++++++++++++++

[@ishandeshpande4843]

1) DFS 2) BFS 3) Union Find 4) Topological Sort 5) Dijkstra's Algorithm Bonus (Not as frequently asked)- 1) Prim's/Kruskal's Algorithm (MST) 2) Floyd Warshall's Algorithm

[@shreddingstuff]

Dude I sincerely can't thank you enough. I'm studying for job interviews and your content is the only reason I feel semi-confident going into them

[@jay-rathod-01]

semi confident lmfao.btw ALL THE BEST.

[@reeshikasingh5615]

Lol I feel you, thank you @NeetCode

[@arpielen]

I make these words my own.

[@dragoshtoader6062]

Did you get the interview?

[@UnspokenThings]

Ur playlist is the reason I feel confident with Graph questions. Thanks Man!!

[@technicalspot1848]

Hey i know bfs ,dfs topo,dijkstra but don't know Floyd warshall prim kruksal right now should i could follow neetcode graph playlists i am tired of just learning new algos i want to solve question to particular these algos after solving some questions i will move to others algos could you guide ?

[@juda550]

The time complexity of graph traversals is actually O(V + E), where V is the number of nodes, and E is the number of edges. Graph traversals are only (n) when the graph is a tree with a fixed amount of children(like a binary tree)

[@anonymoussloth6687]

Can u explain how it is V+E in detail?

[@juda550]

@@anonymoussloth6687 Hey sorry for responding kind of late, but think of the graph as an adjacency list/hash-map. If you want to traverse the entire graph, you need to traverse each key(vertex) and every value (edge). Therefore, the time complexity is O(V + E)

[@simonchristian160]

JUDA FROM CSCAREERSDEV?

[@juda550]

@@simonchristian160 yessir

[@amirnasser7768]

Thanks for the informative videos. Just a small correction about the time complexity of DFS and BFS: it is not O(V) where V is the number of nodes, but O(V+E), where you should consider the edges as well.

[@mohithadiyal6083]

It's a remainder that you are doing amazing 😁👍🏻

[@tahichy9169]

Its really helpful that you categorize every problem and made a separate folder

[@runfunmc64]

i think it’s pronounced dye-kstras algorithm btw

[@MundoTecChannel]

🤓☝️

[@rohitkumar-el9vi]

Witcher 3 also has a character named dijkstra.

[@gnes04]

Dyke straw lol

[@reginafadeeva7881]

You are the best! Thank you soooo much)

[@heen1211]

Because of your content..I feel confident while giving interview...huge respect❤

[@zifanxu522]

Nice topic! Thanks

[@a2xd94]

Great set of problems! Are the problems sorted in order of importance/frequency encountered (IE DFS most important/frequent, Djikstra's algo least important/frequent)?

[@aaen9417]

this content is gold, man

[@ramvenkatachalam8153]

Only bez of Ur playlist is the reason i think i will get a good job . absolutely wonderful videos on DSA . I lov u bro.

[@ChristopherLoverich]

Topological sort is IMHO less obscure than Union Find or Dijsktra's. The latter are more well known by name because they are illustrative for didactics, e.g. Union Find is the first major algorithm introduced in Sedgewick's book as a case study, before returning to a more orderly review of algorithms. Topological sort is, conversely, is an extenstion to a wide variety of well known practical problems like ordering a course schedule or execution of project or (automated) job dependencies. Cracking the Code Interview even argues you should be able to derive it on the spot if you didn't know it (I disagree but shrug). Its a minor point but I think people might see it and think they should study it last, where as IMHO its more expected knowledge than Dijkstra's and also really easy to understand once you've done a few DFS problems!

[@keemkorn]

damn bro you really are just talkin. Power to u brudder

[@gamerclips8895]

The algorithms were created for optimizing software, deliver efficient solutions, but nowadays most of the companies use them to filter out candidates in job interviews and look cool🤦🏽‍♀️, once you get into the company you probably are not going to hear about that never again

[@GabrielAgoncillo-vn9qe]

This is 100% correct.

[@praveenmishra2470]

One of the best interview preparation channel

[@daydrivver2074]

You mention a lot hashset is there any video recommended to learn about that data structure? Most focus on implementation

[@yang5843]

Just fyi, the Di in Dijkstra is pronounced like Di in Dice Thanks for the video

[@CST1992]

Witcher 3 players would know

[@anonymoussloth6687]

Shouldnt topological sort use bfs? Since we would have to print all nodes that are at the same level or depth before going further?

[@NeetCode]

Yeah you're right, I think most people do bfs, but I usually do it dfs which is more simple imo (I used dfs for the alien dictionary problem)

[@edgarcamelo3472]

What about Bellman Ford or Floyd Warshall Algo

[@harryz7973]

would highly appreciate if you can solve 636. Exclusive Time of Functions

[@technicalspot1848]

I know bfs ,dfs,topo sort dijkasta and uninon find little bit too should i start solving questions ?

[@CEOofTheHood]

LEGEND!!!

[@hackytech7494]

Thankyou so much

[@krige]

7:33 isn't topological sort actually identical to BFS?

[@kyriakoskourkoulis1159]

Yeah that's what I think as well🤔

[@fsouza]

In that case yes, but because he picked a bad example.

[@technicalspot1848]

Topo could be extended by both dfs and bfs(also called as khan's algo)

[@adnanelouadghiri6880]

We need a video for LeetCode 1319!

[@huizhao2050]

Hello, for the generic DFS method, should we use void or returning something?

[@abdoulbarry8111]

Why isn't Top Sort BFS since it looks like you are doing level order traversal?

[@SteversIO]

BFS + topological sort is more complex but feels more intuitive (to me). There's more code as you need to manage "in degrees" (the number of incoming edges to a node) and you need a queue (common in BFS).

[@kotsios1998]

time complexity of dfs isn't O(V+E)?

[@pranavsharma7479]

upload more videos on graphs sir

[@hpj1992]

What about bellman ford's algo? Not so common?

[@amitvyas7905]

At 5:22 you say "which is how I was taught" so could you let us know who taught you and how you started to come up with these approaches to solve all these problems?

[@impatientgaming9868]

Good One.

[@admirer.of.cinema9731]

Hi can any one help me here, I used to be python coder but got laid off in April and now I want to switch into more development side I am doing dsa only for sometime what other skill should i focus on

[@ramesh_hegde]

hello everyone,, lets write some neetcode today.

[@tooovisibletosee]

Does topological sort use dfs or bfs? From explanation it’s describing bfs 😮

[@tooovisibletosee]

@neetcode

[@neilmehra_]

You can implement topo sort either way, doesn't really matter. Either use BFS, "remove" edges by subtracting indegrees on vertices and add when indeg[u] = 0, or just build the DFS tree.

[@tirupatirao7521]

Why so less subscribers dnt know

[@IYI_WOLF_IYI]

shouldn't topological sort be BFS and not DFS? (minor error?)

[@neilmehra_]

You can implement topo sort either way, doesn't really matter. Either use BFS, "remove" edges by subtracting indegrees on vertices and add when indeg[u] = 0, or just build the DFS tree.

[@ExamSolutions.e]

thank you . and I would like to see your face

[@BBRR442]

i only hear mouth sounds on this video....