Trapping Rainwater Problem | Leetcode #42

This video explains a very important programming interview problem which is the trapping rainwater problem.In this problem, given an array representing elevation map, we are required to find the amount of water the elevation map can trap.I have explained all the approaches for solving this problem starting from the bruteforce approach to the most optimal approach.I have shown how we can process and highly optimize the time complexity.
CODE LINK is present below as usual. If you find any difficulty or have any query then do COMMENT below. PLEASE help our channel by SUBSCRIBING and LIKE our video if you found it helpful...CYA :)
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[@TW-uk1xi]

This is one of the best explanations I've seen so far on the internet.

[@techdose4u]

Thanks :)

[@EngWorld-nr2ww]

Your patience while explaining is quite appreciable

[@techdose4u]

Thanks :)

[@gsmdfaheem]

Hands down the best explanation on youtube... Better than top creators.

[@mwshubham]

This might be the longest video on your channel. Very well covered. Thank you :)

[@techdose4u]

Welcome

[@abhilashpatel3036]

i did not even notice. Time flies.

[@MdOwaisUmar]

@@abhilashpatel3036 Absolutely, Time flies, but leaves its shadow behind.

[@user-oy4kf5wr8l]

After finding ur videos, i never watch any other channel.... i super like how u explain stuff, and different improved ways to solve it. thank you man!

[@techdose4u]

Welcome :)

[@codingessential91]

great video sir, i had come to understand the O(1) space solution, and your explanation is shorter and much much crisper than anyone else's. keep up the great work.

[@rtan8780]

Dang man, you made a Leetcode Hard problem seem like an Easy. Subscribed :)

[@techdose4u]

👍🏼

[@muwongenicholus2444]

Hehehe, I was thinking the same thing. Some people are natural teachers.

[@sugandhaduhan8707]

Best video on internet for Trapping Rain water.. I wouldn't have understood this problem if I hadn't found this video... Kudos for the great explanation....

[@biswajitsingh8790]

Hands down the best explanation of this problem on the internet. 🙏🙏

[@paramitagorai9087]

Generally dont prefer commenting unless really impressed. This was a great solution and I could code very easily myself. thanks for all the effort spent.

[@techdose4u]

Welcome :)

[@beginnerprogrammingtutoria5053]

An incredibly detailed and amazing presentation. Thank you!

[@YashHalgaonkar]

Your channel is really great! You should definitely have more subscriber than most of other creators who create useless roadmaps.

[@muwongenicholus2444]

You sir, did an awesome job breaking this down and making it simpler to understand. Thank you for your efforts. Appreciate it

[@DK-ox7ze]

Awesome explanation, covering all cases with detail and clarity!

[@techdose4u]

Thanks 😊

[@amitavamozumder73]

It's rare to have a video with zero downvotes! great explanation.

[@techdose4u]

Thanks

[@suryajena1575]

Happy Teacher's day. Really appreciate you as a teacher.

[@gautam4696]

The solution of this problem is very simple but the way sir tells how to approach a problem is amazing .

[@techdose4u]

:)

[@PRUTHVIRAJRGEEB]

This is hands down the best explanation I have seen for this question. I am surprised it doesn't have many views!

[@techdose4u]

Thanks

[@sanketgupta9831]

Best explanation ever with best level of calmness and patience 😊😊

[@01kumarr]

giving all three possible solutions u make life easy. Thanks a lot

[@akashjain4281]

The best explanation for the problems, Ty sir for ur patience and amazing explanations

[@sumeetchawla3545]

Thanks a ton for explaining solution in detail. It's really a tough job. Keep it up!!!

[@sukeshreddy2286]

You are the best. I am now sharing with my friends!!

[@stephc4925]

One of the best explanations! Thanks a lot!

[@techdose4u]

Welcome :)

[@shantanusharma184]

Your explanation resolved all my doubts and i was able to write code by myself after watching your video for 10 minutes.
Thank you

[@techdose4u]

Thanks 😊

[@harikakiran18]

Nicely explained step by step, appreciated it, understood the approach in one go...you deserve more subs & views...hope you will reach there ..:)

[@techdose4u]

Thanks ❤️

[@mridulsemwal1396]

No one explains like this.
Loved your videos

[@techdose4u]

Thanks 😊

[@chandrachurmukherjeejucse5816]

So far the best explaination. Thank you so much sir.

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Thanks for this beautiful video, your explanation made me code myself... At the end of 16 min of the video, I understood and coded in python.

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You Deserve more than a million subscribers for such a great content!

[@techdose4u]

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[@hnsc1]

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Well done

[@flyingcanopy5611]

I watched many videos to understand the concept of two pointer approach.. But after watching this video, It became so clear to me.... Next time if I am unable to solve any question I will come to this channel first... This is a very underrated channel..

[@techdose4u]

Thanks :)

[@varshaprajapati6566]

thankyou so much for this video! you just made this hard task quite easy.

[@pkboolean]

thank you for this, this is extremely well explained

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Thanks

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Excellent explanation!
Your channel will definitely grow a lot

[@techdose4u]

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Keep going 👍

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Thanks alot! I was struggling to understand the logiv but now its clear

[@techdose4u]

Great

[@sujitha2339]

Clear explanation!! Thanks bro

[@kushagrashekhawat8227]

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[@techdose4u]

thanks :)

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Awesome Explanation, better from other CZcamsrs

[@techdose4u]

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[@aniketroy03]

Great video sir!! What an explanation! Keep uploading such videos 🙏🙏

[@techdose4u]

Welcome :)

[@atjhamit]

Really good explanation! Thanks a lot.

[@NaveenRawat51]

awesome explanation, the way you explained corner cases are great. keep it up

[@techdose4u]

Welcome :)

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Awesome explanation . Even kids can understand after watching this video. Thank you very much

[@techdose4u]

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[@krupaharan9406]

This saved my day :-) Thank you very much

[@techdose4u]

:)

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Great explanation, thank you.

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When the content is so good, subscribing and liking are on autopilot.

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very clear explanation!

[@trueindian03]

This was an excellent explanation.

[@Harsh-og5xr]

loved that o(1) space method

[@athisii_ekhe6167]

you made it easy. Thank you.

[@cs-ope]

Great explanation!

[@MohitKumar-rq8hv]

TC =O(n)
SC =O(1)
=> 24:25
superb explaination

[@techdose4u]

Thanks 😊

[@milenitrivedi7561]

great explanation !!

[@santhoshmedide5279]

The last solution where time-O(N) and space-O(1) method is amazing. Came here after many leetcode solutions!

[@yashkhandelwal6588]

Thank you so much you explained these questions by previously known methods because others are making it very complicated for reducing code size()

[@techdose4u]

Welcome :)

[@akshitjain2906]

amazing explanation bro!

[@SaiKumar-if4lh]

Top notch explanation 👍

[@CodeSuccessChronicle]

Thank you so much for doing this on my request.... best bro...

[@techdose4u]

Welcome :)

[@elitesharma817]

Right at 21:35 I stopped and boom my code got accepted, thanks a lot bhai, I was trying to solve with 2 pointer approach as well but couldn't deal with the water-level stuff, which you made so easy to understand and grasp, and not just that also for improvising code in such an awesome way with 2N Auxiliary space. Again thanks a lot bhai

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Nobody cares thou...keep coding

[@dayanandraut5660]

excellent explanation. awesome solution.

[@PRASHANTKUMAR-xs9pk]

In every Questions , too much concept as well as hidden cases . When i want to try same questions after 4 days or a week i got stuck but your explanation make question easier for me. ::))

[@techdose4u]

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[@huansir1922]

thank you for your explain , from simple solution to better solution !

[@techdose4u]

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[@spaceship-rl5fp]

Excellent Explanation

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I bet this vdo has got the best explanation for the two pointer approach...thanks a ton TechDose😊

[@techdose4u]

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[@sumit180288]

Very good explanation

[@elenamikhaylova4287]

nicely covered thank you

[@krishnananddubey2870]

Just explained it calmly loved that.🤗

[@techdose4u]

Thanks

[@gurubalaji5611]

Great explanation sir..hope expecting more videos from tech dose..

[@techdose4u]

Sure. I will keep uploading :)

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Thank you , Just THANK YOU

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[@techdose4u]

Thanks :)

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Great explanation

[@ayeshaadhikari6123]

Thanks a lot Sir!

[@neerajpandey7273]

I had seen your video of solving the area of histogram ..so first thing came in my mind to take 2 stacks to get left and right max ...while writing the code I realized that I can solve this without stack .... after that I saw your complete video and got o(1) space method ... this is crazy

[@techdose4u]

😂 hahaha. Very nice to see you apply the concepts of my previous video :) But there is always someone better than you 😉

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[@rachanasingh7047]

Best solution explaination to this problem. 🙌

[@techdose4u]

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[@techdose4u]

Thanks :)

[@RayTayek]

very nice. thank you

[@viveknandan4950]

Nice explanation.

[@ravisankarmaruramesh8112]

Index starts from 1 to arr.len-1
Totalwater+=Math.min(leftmax of current index element, rightmax of current index element)-current index element

[@techdose4u]

Nice 1 liner :)

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You are very easy and nice to understand.

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Best explanation sir. Thank you

[@techdose4u]

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You are legend 🔥🔥🔥

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amazing crystal clear
explaination

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Thanks

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Best explanation

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Thanks a lot!

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Very nice explanation 👌thank youu

[@techdose4u]

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Simply Amazing!!

[@techdose4u]

Thanks ☺️

[@rajivsarkar277]

Ur patience is appreciable

[@techdose4u]

Thanks :)

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Nice explanation. Thanks!

[@techdose4u]

Welcome :)

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Nice explanation sir......you are doing a great job

[@techdose4u]

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Such a great explanation

[@techdose4u]

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what a coincidence that we both were working on the same problem.

[@techdose4u]

:O

[@khushbukareliya8999]

Best Explanation.

[@techdose4u]

Thanks