Trapping Rainwater Problem | Leetcode #42

[@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 :)

[@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.

[@gsmdfaheem]

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

[@大盗江南]

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 :)

[@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.

[@saleheen12]

Man, you just made a hard leetcode problem so easy that I just coded it all by myself successfully.
Can't thank you enough

[@techdose4u]

great :)

[@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.

[@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 :)

[@amitavamozumder73]

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

[@techdose4u]

Thanks

[@gautam4696]

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

[@techdose4u]

:)

[@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....

[@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 😊

[@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

[@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 :)

[@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]

Great :)

[@YashHalgaonkar]

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

[@suryajena1575]

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

[@MohitKumar-rq8hv]

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

[@techdose4u]

Thanks 😊

[@biswajitsingh8790]

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

[@ajaygonepuri2285]

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

[@techdose4u]

Thanks :)

[@mridulsemwal1396]

No one explains like this.
Loved your videos

[@techdose4u]

Thanks 😊

[@kushagrashekhawat8227]

I've watched many of your videos. Your explanations are always very easy to understand. Thank you for creating these videos; you are doing so much good.

[@techdose4u]

thanks :)

[@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

[@depression_plusplus6120]

Nobody cares thou...keep coding

[@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 😉

[@neerajpandey7273]

@@techdose4u =D =D

[@muwongenicholus2444]

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

[@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 ❤️

[@DK-ox7ze]

Awesome explanation, covering all cases with detail and clarity!

[@techdose4u]

Thanks 😊

[@stephc4925]

One of the best explanations! Thanks a lot!

[@techdose4u]

Welcome :)

[@Black_Diamond0104]

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

[@techdose4u]

Welcome 😄

[@01kumarr]

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

[@sanketgupta9831]

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

[@manojbhatt8424]

brooooooooooooooooo best explaination ever

[@techdose4u]

Thanks :)

[@ayushsrivastava830]

Awesome Explanation, better from other TH-camrs

[@techdose4u]

Thanks 😊

[@venup2813]

Most underrated channel

[@ravikumar-kh9gi]

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

[@techdose4u]

Welcome 😁

[@kambalavijay6800]

Techdose to me is a game changer

[@harishkandikatla9791]

Excellent explanation!
Your channel will definitely grow a lot

[@techdose4u]

Thanks 😊

[@coderart__2802]

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.

[@rajivsarkar277]

Ur patience is appreciable

[@techdose4u]

Thanks :)

[@chandrachurmukherjeejucse5816]

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

[@hnsc1]

Thank you for this video! I appreciate you drawing out the base cases and explaining everything in detail. This is definitely the most helpful video for this problem :)

[@sukeshreddy2286]

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

[@akashjain4281]

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

[@jiosim1377]

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

[@techdose4u]

Great

[@PujaKumari-rp5sg]

sir you explained very nicely step by step 👌👌👌

[@huansir1922]

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

[@techdose4u]

Welcome 😊

[@NaveenRawat51]

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

[@techdose4u]

Welcome :)

[@beginnerprogrammingtutoria5053]

An incredibly detailed and amazing presentation. Thank you!

[@basiljacob3894]

Very well explained sir , your explanation for this question is crystal clear. I really liked this problem it was very intuitive

[@techdose4u]

Thanks :)

[@sumeetchawla3545]

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

[@tejeshd5278]

Very underrated 👍🏼

[@techdose4u]

:)

[@calisthenics-]

Champ tech dose🙏 👏
Well done

[@chhavimishra3469]

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

[@nikitakushwaha9572]

You are very easy and nice to understand.

[@techdose4u]

Thanks ☺️

[@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 :)

[@gamingKlips99]

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

[@techdose4u]

:O

[@rachanasingh7047]

Best solution explaination to this problem. 🙌

[@techdose4u]

Thanks :)

[@aniketroy03]

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

[@techdose4u]

Welcome :)

[@Harsh-og5xr]

loved that o(1) space method

[@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

[@techdose4u]

Thanks

[@gurubalaji5611]

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

[@techdose4u]

Sure. I will keep uploading :)

[@bloody9162]

It's sad TH-cam has hidden dislikes on a video, stops good videos like this from showing up first. Thanks. 38k views and 1.2k likes? c'mon guys hit the like button.

[@techdose4u]

Thanks 😊

[@simrankak7045]

amazing crystal clear
explaination

[@techdose4u]

Thanks

[@santhoshmedide5279]

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

[@harshavarthinivr9688]

Very nice explanation 👌thank youu

[@techdose4u]

Welcome 😀

[@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 :)

[@sandeepkharola6463]

Great work
Keep going 👍

[@ethanzhao5729]

Your explanation fits the process of how to solve a problem -- from observation of cases to generalization to optimization to final code. Pure memorization of the solution without following this process is not helpful to interviews

[@CSe_IT_Guy]

Best explanation 👏

[@techdose4u]

Thanks ☺️

[@krishnananddubey2870]

Just explained it calmly loved that.🤗

[@techdose4u]

Thanks

[@paragroy5359]

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

[@techdose4u]

Thanks :)

[@playing_rhythms2660]

I think in the last condition it will be (l

[@egor.okhterov]

As we go from left to right `max_left` could only increase (or stay the same).
As we go from right to left `max_right` could only increase (or stay the same).
That is why when we move pointers L and R, `max_left` and `max_right` compete with each other. First one gets larger, then the other gets larger, then the other gets larger. And we swing from one side to the other side moving pointer L and R closer to each other.

[@TheBikerDude2024]

Excellent explaining.

[@sumit180288]

Very good explanation

[@abdulkhadarm6050]

Very nice explanation🎉

[@techdose4u]

thanks

[@MousamiDeshmukh-g8k]

I did not understand one thing @TechDose . Can you please tell me why are we choosing to go towards LEFT when left height is less and why to right-- when RIGHT height is less ?

[@khushbukareliya8999]

Best Explanation.

[@techdose4u]

Thanks

[@nareshh74]

Thanks for the video. Can u logically explain how u chose 2 pointers approach?

[@monikavaid5083]

Very good solution!,

[@techdose4u]

Thanks 😊

[@sujitha2339]

Clear explanation!! Thanks bro

[@spaceship-rl5fp]

Excellent Explanation

[@ayushmantiwari7547]

No doubt why this video has no dislikes.

[@techdose4u]

🤗

[@shashirajitagi616]

Thanks for such an excellent explanation. I had one query, I think the code won't give the right sum for the array {4,3,1,5,0,5,0,3}. Can you help here?

[@prathameshmore5262]

@TECH DOSE 1st approach is brute force approach right

[@vaishaligoyal7478]

Simply Amazing!!

[@techdose4u]

Thanks ☺️

[@prakharagarwal6237]

Nice Explanation! Thanks!

[@dayanandraut5660]

excellent explanation. awesome solution.

[@akshitjain2906]

amazing explanation bro!

[@huseyinbarin1653]

very clear explanation!

[@basictechs6634]

Great explanation, thank you.

[@prasantharavindramesh1078]

@ techdose bro fantastic explanation
Just a follow up question
If the bars are of variable width then can I use an array of structures to store the length and width of each bar and calculate the amount of water trapped or is there any other approach?

[@techdose4u]

Width doesn't affect the max heights on left and right. Instead of just taking ht, just multiply ht by current bar width. That's it. Same code will run

[@trueindian03]

This was an excellent explanation.

[@cs-ope]

Great explanation!

[@yuvrajagarkar8942]

very nice explanation thank you 💞, How do we develop this intuition sir ? , i mean the logic at the end was a bit tricky how can one spontaneously come up with such solution??

[@CodeSuccessChronicle]

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

[@techdose4u]

Welcome :)

[@athisii_ekhe6167]

you made it easy. Thank you.

[@krupaharan9406]

This saved my day :-) Thank you very much

[@techdose4u]

:)