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Regular Expression Matching - Dynamic Programming Top-Down Memoization - Leetcode 10

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what problems do I need to practice first before solving this?
Comment from : @sujitachaudhary7089

One of your best video ❤
Comment from : @AbhiudaiShahi

goat
Comment from : @alifrahman7099

should be take not take , and only say star when there is a star, felt like there was an error in the explanation at 11th minute
Comment from : @ShubhamDineshBafna-t5t

F**king genius!
Comment from : @Box-iq1zj

had to watch it twice it just clears concept can't thank you enough Neet
Comment from : @an4220

03:20 * and empty string should return False
Comment from : @gyaan3101

Loved your solution, Neet I was breaking my head to get it working Thanks for the neat explanation and a great walkthrough :)
Comment from : @manivannansivaraj7324

Thanks!
Comment from : @mfaani

I'd always tend to avoid using "i" and "j" because they look very similar in most fonts Use "i" and "k" to improve readability -> remember: code is read heavy
Comment from : @cchexcode

Thanks its a pretty difficult problem
Comment from : @paneercheeseparatha

Thank you, Neet! Great Explanation!
Comment from : @akhma102

Thanks
Comment from : @michaelc3781

solve in one linebrreturn bool(refullmatch(p, s))
Comment from : @chizhang9135

Wow man your explanation is just fantastic!
Comment from : @for_whom_the_bell_tolls

just a clean explanation amazing
Comment from : @nishapaila7870

Instead of optimizing it with cache, I've got an almost identical result (1300ms->50ms) by simply ensuring you don't process subsequent stars So if there is a*a*a*, you'd only check it once Now the cache seems obvious, but that addressed directly the most compute intensive cases :) Funny to see how it's same efficient Using both would probably improve it even further
Comment from : @kocot

GOAT
Comment from : @samridhshubham8109

That's the ugliest solution as well as finest understanding theoritical video
Comment from : @Plutonium_357

You made it look so simple Thank you!
Comment from : @saadkhan4049

Perfect explanation! Thank you And the code looks good
Comment from : @juliramoos

how did he changed the leetcode code editor to this color
Comment from : @sameerkumar-uq2ic

What an explanation sir ji❤ After this, I was able to solve wildcard matching by myself
Comment from : @rahuljain281

i dont think so if memoization was actually ever used
Comment from : @iharshgarg

i checked so many videos of this problem but there's simply no compedition to you bro keep the neet work up bro/>
Comment from : @iharshgarg

Thank you for the very good video
Comment from : @purnimadas768

but I got a doubt how are we looping the string if we ae not using any loop like it will check all the conditions for 1 time but how is it looping ??? can anyone help?
Comment from : @Team_sih

Great explanation! :) @NeetCode what tool do you use to write and draw ? brAny specific brand, I'm looking for this kind of tools
Comment from : @jonathanandres1657

you need to explain how the cache actually saves time How does storing the indexes along with a bool value save any time?
Comment from : @emretekmen1602

Thanks alot for helping me understand the issue, I was doing the bottom up and solution was failing in leetcode on last 2 test cases After watching this video I understood we need to do bound check on index "i" - stupid of me missing such a basic thing Now solution worked
Comment from : @santoshr4212

the question description feels really incomplete without your explanation , thanks a lot
Comment from : @tanaysingh5348

If there is one thing which I am not sure is how will the subproblems repeat If anyone has any intuitive way, pls let me know
Comment from : @sauravchandra10

You make hard problems very easy Thanks for explaining
Comment from : @sauravchandra10

I think the time complexity would be O(N^2M) and not O(N*M) since we have to iterate through the s in case of "*" Please do correct me if I am wrong Thanks!
Comment from : @Chirayu19

How easy you make a hard problem is unbelievable !!!!!! Salute to you
Comment from : @VishalKumar-kr9me

Very good explanation, love the channel!
Comment from : @MutuallyBro

18:19
Comment from : @meto4545

Very good explanation thanks!
Comment from : @aldogutierrez8240

For anyone getting confused with the solution to this problem, I found the bottom-up approach to be much more intuitive Just my experience, I know everyone is different
Comment from : @jacques-dev

Could you explain wildcard matching, a similar problem to this one?
Comment from : @ashkankipati

this problem took me soo much time to understand, thank you dude
Comment from : @comander47

this is called Codeagasm Mind blowing
Comment from : @axay30

I've recoded your solution and it's brilliant However, I've been trying to follow the stack trace of the program execution to convince myself when the first if statement would execute "if (i, j) in cache: return cache([i, j])" I know it does because I tried removing it and got a TLE error o Leetcode, but I don't see when it would be needed as we always progress into a deeper DFS and cache Would appreciate an explanation if you could please! Thank you
Comment from : @kaartiknagarajan5009

not understand why we need a cache dictionary
Comment from : @連尼克

Thank you for the explanation I thought according to the problem statement, 'c*' cannot be empty, which was very misleading by Leetcode
Comment from : @zl7460

can you solve it using only re module in python?
Comment from : @mirshodoripov1035

The dramatic decrease in time taken to execute after using cache surprised me brThanks for the explanation and code
Comment from : @pranavkashyap8610

Super awesome explanation NeetCode 🎉Thanku
Comment from : @JameS00989

Super thanks for this!
Comment from : @taroserigano6546

This explanation makes the whole process clean and simple
Comment from : @袁丽君-s7c

man love ur explanation ,great man ,no words love u man
Comment from : @nagasivakrishna5660

great explanation without sophisticate dp, can't thanks more!
Comment from : @chongwen

Thank you so much
Comment from : @pulakammalathy6968

Thank you so much for this After weeks (!) of trying to solve this problem on my own, I decided to look it up and lo and behold -- the solution involves a bunch of stuff that I have never heard of I feel a bit better (and I need to learn about Dynamic Programming now) >_< Thanks again for the elegant, succinct solution
Comment from : @Whatthetrash

To be honest, I never would have even guessed that this is a Dynamic Programming problem Once you started explaining the decision tree, it ALL made sense Thanks for teaching me something new!
Comment from : @jimwu3856

thnks bro i was not getting how to solve this , this is same as wildcard matching with a twist
Comment from : @pranavsharma7479

Appreciate your explanation thank you
Comment from : @thisissheraf

i seriously love your video i swear you dont waste time i love it
Comment from : @notsadsisyphus6224

I really appreciate your explanation, so clean, so logical!
Comment from : @ruizhu5295

Can someone explain why we dont add cache for line 11 & line 13 the two base cases?
Comment from : @scottchen2094

recursion & caching 😊
Comment from : @blackychauhan

Amazing explanation Really thankful for your great efforts :)
Comment from : @sumeetchawla3545

will it work with s: aaa, p: aab*a*c*a ??
Comment from : @saikat511

I was struggling a lot with this question Your video cleared my doubts Thanks for sharing!
Comment from : @buttercup5029

very very tedious, not recommend
Comment from : @weidazhu3519

👍👍👍
Comment from : @shivamverma-ml8bk

Which tool do you use to draw all these explanations?
Comment from : @MohitJayee

Best explanation ever!
Comment from : @lingyunsu1589

OMG, the question looked so tough, but you made it soo easy !! Another awesome explanation Great fan of your NEET coding style :)
Comment from : @dollyvishwakarma2