Recursion - Level 1 Questions (Theory + Code + Tips)

[@KunalKushwaha]

DSA + interview preparation playlist: kzbin.info/aero/PL9gnSGHSqcnr_DxHsP7AW9ftq0AtAyYqJ

[@aqsa537]

Just the intro to recursion video was enough to solve all the questions in this video! I'm a beginner to recursion and felt like I've been doing this for months! *For people watching in future blindly trust this bootcamp!*

[@KunalKushwaha]

You're very welcome!

[@shreyasingh4680]

@@KunalKushwaha we can count 0 without helper function int cntz(int n) { if(n%10==n) return 0; if(n%10==0) return cntz(n/10)+1; else return cntz(n/10); }actually i am learning c++but in order to understand the approach i am here and its just amazing. thank u!

[@venkateswararaothotakura945]

@@shreyasingh4680 cntz(int n, c) If(n%10==n) return 0; rem=n%10; if(rem==0) return(n/10, c=c+1); return (n/10) ;

[@Rajdweep]

@@KunalKushwaha one qs bro if we r keeping the function void why are we taking extra functions extra variables etc?cant we just print n%10 and then write func(n/10) in the else part?i tried it and its giving same output in much less steps.

[@shreyasgosavi9647]

​@@Rajdweep Recursive problems can be solved in different ways, there is no single way to solve it. What's important is understanding the concept !!!🙌

[@piyushkhandelwal1662]

I dont care what anyone say about kunal the only thing i know is that kunal is one of the best teacher and a mentor for students like me who cant afford udemy ot another paid course

[@rakeshsagar9510]

There is no doubt about it. The reason why he has low subscriber base is he teaches in English unlike other others who prefer teaching in Hindi.

[@BABATUNDE-h7d]

500rs afford nahi kar sakte??

[@hudahabib-zq2oc]

From Pakistan, I started this boot camp 1 week ago, and boom! I have improved my logical thinking more than I have learned in the past 11 months! The best lectures!! very dedicated and knowledgeable instructor. Excellent💯

[@anshulprakash6564]

Boom word was quite predictable

[@itsdivanshugarg]

no offence but you could have just said that you didnt do shit in those 11 month lol😂 even if you had studied 40-60 minutes a day for 11 months, there is no way in hell you can improve more than that in just 1 week

[@ABHISHEKSHARMA-jj5jh]

bro's recursion videos are even longer than the other youtubers full java course. Excellent.

[@mohamedirshaathm32123]

true

[@lokesh8660]

check durga software solutions for java

[@Aryan_agarwal830]

there is a difference between only java course and java + dsa course

[@vedantboddula2379]

where is first video of recursion

[@kaushalkawade3623]

Hey Bro you just changed my perspective about recursion, I am the one who resigned programming at the time of recursion. But your course gave me lots of confidence about recursion so thank you so much you are doing great work.

[@rahulkrishna8247]

The same happened to me as well Thanks Kunal!

[@DWEthiopia]

This is the best playlist for recursion in all of KZbin! Great job!

[@vedified-spiritual7034]

After watching the previous videos thoroughly, i did not face problem in any of the question of this one. You explain everything so well. You are a piro!😊

[@devanshdewan2597]

the organization of the questions is perfect . the questions have been tailored in such a way that it forces a student to learn deeply about recursion .

[@anshgupta6754]

59:25 alternate method (C++) int noOfZeros(int n){ if(n==0){ return 0; } if(n%10!=0){ return noOfZeros(n/10); } return 1+noOfZeros(n/10); }

[@Shubham-ek7jv]

Million heart smiles come when ur videos come

[@mcharith4328]

By seeing the last question, I understood how to approach the problem like kunal, and done it. This is literally the best course one can ever get. Thanks Kunal...

[@kage-musha1702]

i was anxious if you ever abandoned this course , i geniunely got tears when i saw a new DSA video got uploaded thanks alot boss :D

[@KunalKushwaha]

I will complete it this month

[@codingweb3904]

@@abhishekc3556 i guess abdul bari sir, his teaching style is similar to abdul sir's teaching style.

[@codingweb3904]

@@abhishekc3556 yeah thats correct

[@yashtalks7250]

@@KunalKushwaha Bro lakhs of students career is dependent on this course... A big thanks from all of us.....

[@swastikpatro6436]

@@KunalKushwaha It's been over a month, the course is good, please upload more videos..

[@techlearnwithsharmaji3204]

Isse accha aur best recursion ka video ho hi ni skta pure youtube pr aisa video available ni h jo itna deeply samjhay aur aapki mehnat ko dekhne se lg rha h ki aap hme smjhane k liye kafi preshan to bhaiya mai apko bta du ki maine itne videos dekhe kisi ne bi itna acche se ni smjhaya . Aur apke video se maine recursion ko ekdam clear aur easy way me smjh lia . Thank you bhaiya❤❤❤ love you Aap aise hi videos bnate rho ❤❤❤❤❤❤❤ ❤

[@yourdailydoseofmeemeee3006]

Just finished the video and was able to do all the questions by myself just cause I revised the notes that I made in the recursion basics video. What a brilliant way to teaching man! Hats off to you!

[@harshavardhangulla4058]

Best content from the great mentor.. with a lot of patience.. ❤️

[@NSEERADIVYA]

Until I saw this.. I fear those terms like functions, recursion.. before. But after watching this.. As a beginner, Iam understanding better.. it works while writing on paper.. The word THANKS not enough. We are blessed for having you. 🙇. Forever your Student.

[@adityaram7408]

53:51 by using another arguement : class reverseNum{ private static int reverse(int n,int Ld){ if(n==0) return Ld/10; return reverse( n/10 , 10*(n%10+Ld) ); } public static int getReverse(int n){ return reverse( n/10 , (n%10)*10 ); } }

[@piyushgupta6290]

Maza aayaa....aur ye maza har programmer ko lena chahiye😆😆😍👍👍👍👍👍

[@ayeshasolanki5386]

Kunal, it's just just awesome, whenever you say it's the best course on DSA then you mean it, will recommend everyone to give it a try at least, and I promise you won't regret it later

[@KunalKushwaha]

Thank You

[@xaviball2911]

you are intern at google?

[@mr.6889]

48:37 public static int numRec(int num){ if(num == 0) return 0; int log = (int) Math.log10(num); int pow = (int) Math.pow(10, log); return (num % 10) * pow + numRec(num / 10); }

[@radhekrishnamishra5371]

Like you are saying you will upload all the remaining ds lectures within this month, I can guarantee you will have more 100+ subscribers from my college only . Also you will eventually cross the 100k subscribers marks definitely in this month only 🔥🔥🔥

[@radhekrishnamishra5371]

Full support to you bro,bcuz of you I am attempting Java questions I owe you and I will make up it by adding 100 subscribers in your channel brother

[@udaysingh2929]

Not completed the course 🥲

[@codeman0017]

@@udaysingh2929 ongoing when ever he is free he will do just like uploading stacks and queues in last 2 months

[@Yasmin-i7d1h]

amazing youtube video ever on this topic, really appreciate how u could make this complex topic easier like child's play

[@Hariharan0606]

Crystal clear explanation , Got the hint of Math.log10 and solved this question myself reverse(4326) using recursion function reverse(n) { if((n%10) === n) return n; const numberOfDigits = (Math.floor(Math.log10(n))+1); return (n%10 * Math.pow(10, (numberOfDigits-1))) + reverse(Math.floor(n/10)); } console.log(reverse(4234));

[@VinodKumar-fn2iq]

I wish this course was a lil bit fast paced.......I'm really in need 🥺

[@allaboutgamimg7976]

@@suhaspatnaik Bro Link?

[@KunalKushwaha]

Will be completed this month

[@allaboutgamimg7976]

@@KunalKushwaha Thx bro for your hard work

[@himalbajgain2280]

This video is outstanding. I am not skipping any advertise that comes while I am watching this.

[@vigneshwarapalanisamy2242]

class Solution { public int numberOfSteps(int num) { if (num == 0) return 0; if (num % 2 == 0) return 1 + numberOfSteps(num/2); return 1 + numberOfSteps(num - 1); } } 100% fast with 86% efficient memory management :)...thanks kunal

[@aswinbarath]

The more we wait for future lectures, the better it gets 🥳

[@rajarshichaudhuri]

Never thought that after purchasing paid courses from GFG and Coding Ninjas I will come here and clear out my doubts on recursion. I think the differentiating factor is also your crystal clear art of communication ....Thanks for making this video exist free for everyone.

[@kishanchandrahaldar342]

Kunal Bro You are one of the best tutor online I have ever found learned a lot from you thank you for being there !!!

[@0xDomain]

To be honest your videos on DSA are helping me a lot. I felt stupid when I started learning recursion, like why could i not understand. But after watching the first two videos I know that it requires time and dedication with exceptional teaching which you successfully executed. I really thank you and appreciate you putting in the time to help us understand DSA

[@Praneeethh]

woahhh !! Really great never thought recursion will be this easy.Kudos to you brotherr!

[@UnyimeUdoh-ny3lp]

Bro, the concept of an helper function is a game changer

[@AdityaKeshari-p9t]

Kunal bro its a Excellent Course ...im litreally feeling very much fun while doing this recursion problems ....And because of your Guidance i am able to do it on my own ...ThankYou SO Much....

[@ankit_1012]

You are the best teacher i have ever came across in my life.. ❤

[@parthasarathiroy4293]

54:10 Without using any helper function or extra variable, reversing a number can be done. My approach>>>> public static int reverse(int n) { if(n==0) return 0; return (n%10)*(int)(Math.pow(10,(int)(Math.log10(n))))+reverse(n/10); }

[@subisuresh7564]

Math. Log10(n)-1

[@shafaq-here]

Kunal your teaching style is alot different from hundreds of high qualified professors out there . Just finished with the lecture , it was really amazing, learning how to approach these problems . Good vibes only 😌😌

[@dark-knightCoder]

hey brother you change my cooding skills ,thanku so much your teaching style is awesome

[@pankajthakur-zd5wl]

Great Videos on Recurison ❤

[@FarhanKhan-cx4ke]

1:08:41 Q-10: Count Steps. Just do this public static int countSteps(int n){ if(n == 0){ return 0; } if(n % 2 == 0){ return 1 + countSteps(n / 2); } else { return 1 + countSteps( n - 1); } }

[@alonbrim]

Another great video from Kunal!! Very clear, and thought step by step! Thank you very much!

[@dawncoming896]

one of best lecture on recursion have ever seen(last example)

[@hussaingagan9196]

we can also solve the count zeroes question without taking an extra argument or helper function like the below way: static int count(int n){ if (n == 0){ return 0; } if (n%10 == 0){ return 1 + count(n/10); } return count(n/10); }

[@ihsannuruliman3656]

with the helper the runtime and memory usage are usually better

[@OvaisKhanday]

Q9. Count the number of Zeros in a number. I love the lectures from Kunal. I actually came up with a better solution for the problem: public int count0(int n) { if (n == 0) return 1; if (n

[@punyakgoswami8119]

You beauty!! Never ever felt this confident after watching your recursion videos :)

[@swaroopchitiprolu4771]

Best Course on DSA you ever find in the market! Thank You Kunal for taking the time and creating the course.

[@amithhd]

To be honest your videos is 🔥 and helping me a lot. I felt stupid when I started learning recursion, like why could i not understand. But after watching the first two videos I know that it requires time and dedication with exceptional teaching which you successfully executed.

[@ajak968]

Was confused with submissions in Leetcode, the helper function cleared everything. Thank You!

[@ogfactss]

Way #3 for question 7 and way simple static void printDigitsRev(int n){ if (n/10==0){ System.out.print(n%10); return; } System.out.print(n%10); System.out.println(); n = n / 10; printDigitsRev(n); } love your teachings your proud student

[@projectsdb4034]

I solve the last question by myself though its easy but approach was same as you taught, You are great teacher I wish and hope you publish video everyday

[@Vikkyblogs80]

He kunal you are teching good but I read that we can check even odd using n&1==0 from a channel called Kunal kushwaha. Bhai loved your videos.

[@zafeerrangoonwala4741]

It's a great video! I was quite skeptical about recursion but this video has boosted my confidence! Kudos to you!

[@AkshatGairola11A23]

One of the best tutorial of DSA in youtube😊

[@abhinjr4918]

This man is fkkkkinnnnngggg legend..... I cant believe i solved in a row every problem without seeing his solution 😮

[@bhagyashri2712]

Kunal is Gem of Person ❤️ Doing such a great work which is helping thousands of students right now !!

[@parvishrao6414]

Video description is 100% Justified !!!!!!!!! - These are questions that will build the foundation of various concepts and improve the thinking process.

[@krish2464]

never before and ever after of this type of teaching 👍👍👍👍

[@KunalKushwaha]

Thank you

[@thelazymim9338]

Excellent Kunal !! You are just amazing. You try really really hard to make us understand in free. Can’t thank you enough. For your such hard try to make us understand unlocks our potentials to solve a problem. Just a new subscriber of you but still now I also tried to solve the Reverse a Number in a different way. static int reverse(int n, int res){ if(n==0){ return res; } res = res*10 + n%10; return reverse(n/10,res); } caller function: reverse(1324,0)

[@nikhilteja8171]

Excellent lecture kunal bhaiyya!... This video helped me a lot... Thank you so much... appreciated...!

[@Setchuko]

kunal within a week i completed 27 videos now u r the best teacher.....

[@chethanm6713]

maybe Kunal is feeling that we are finding difficult to understand recursion but we know this quality of teaching and content is not available anywhere. Hats off to ur dude

[@PriyaSingh-zb5wn]

The examples provided are indeed suitable for beginners and can help them understand recursion more deeply. It helped me to get better understanding of the topic.😃

[@mohamedsaiidouertani3568]

you are amazing kunal as per usal , but in Q7 the second way we can do it witout a helper function public static int reversenum (int n){ if(n

[@abhishekpundir5941]

Thanks Kunal for making this recursion playlist...you have made recursion so much understandable. And to all who want to understand how actually recursion works then this is the only playlist you need. I haven't seen anyone who is debugging and showing all the process behind the scenes. And now I can correct my mistakes myself by debugging and it's a great feeling...so again thank you brother for making amazing content. You are doing great work...keep going and I hope you will continue and complete this playlist because I don't want to learn from any other resources...lol

[@sarvarjuraev1376]

My friend suggested this course and with the intro I am getting much more than I expected. Thank you Kunal )

[@video_editing_satvick]

Bhai sach bolu toh bht easy lag raha aapki wajah se, thank you so much

[@Helly_Patel]

Thanks for teaching us like no one did till now!! One small request, please make lectures on dynamic programming as well!!

[@reyyisuresh8317]

I found it very helpful. The way you are explaining is so good. I was able to understand the suggestion "pen and paper" was working. Thanks for that.

[@coolengineering3486]

Simply the best on you tube, thank u so much for all the hard work you put to do all of this in so much detail. Appreciated a lot.

[@parul8334]

I have a lot of fear regarding Recursion. But now it seems easy peasy. Thank u so much.

[@PranjalChalak]

First time learned recursion questions that are beyond finding factorial or fibonacci !!

[@edmundtetteh8885]

Thanks, Kunal, I just followed your teachings while coding in JavaScript, and even though I believe you use Java, I could do exactly with your pseudo code provided in your worked examples. Thanks, a lot

[@c114sanakhan6]

As a result of his efforts, I'm enjoying my least favorite topic now. 😊 I'm glad that I chose this playlist for my interview preparations

[@tharunmadamanchi1280]

Recursion is never an easy topic but you made it easy, Thanks my brother ❤

[@tanu_mishra4413]

Hey kunal! The way of your teaching is surely amazing and you know what no-one i repeat no one can explain things like you... lastly thnx so much for this bootcamp....you killed it ❤

[@TarunSai-i7b]

1:05:00 If we give input number as zero it should return 1, not 0 because zero is also a number and no of zeroes in 0 is 1

[@sanjaykumar-ki9hv]

static int count(int n) { // Special case: if the number is 0, return 1 if (n == 0) { return 1; } return func1(n, 0); }

[@prateeksingh6018]

Amazing explanation kunal ! I easily solved the questions on my own then checked your solution, they match quite a lot.

[@veeee5577]

recursion is has never been so easy to me thanks for making it so easy kunal

[@ritikakapoor4583]

Thank you so much, Kunal. We really appreciate you taking your time and putting in efforts to provide us with the best content. I was actually able to solve all the questions before you explaining the solution. This is how great of a teacher you are.. Hats off!!!

[@senseiAree]

I really loved your videos man. My OCD triggered when you said 30:55 instead of addition we can do production... But jokes apart.. I am still watching your videos and it is really interesting. I am planning for DSE Examination and this is the best video I've found so far.

[@nalinithondapu9240]

Because of these classes understood the recursion very easily. You are awesome Kunal. Thank you very much for this. :) :)

[@rohitchilhorkar8114]

The introduction to recursion video is enough to solve all the questions... Great video excellent content. Keep it up bro!

[@raviraj-xq4ue]

the last two question gave me GOOSEBUMPS🔥

[@surajpradhan4532]

Alternate simple solution using C# for Count Zero in a number without passing count as argument - int InternalCountOfZero(int v) { if (v == 0) return 0; int count = v % 10 == 0 ? 1 : 0; return count + InternalCountOfZero(v / 10); }

[@raghavjha2914]

Thank u bhaiya I m just stuck on the topics with 3 month but now i am feeling right to move forward with you on this bootcamp

[@mdiftekhar6876]

The flow of explanation was lit and please I request everyone don't be sacred by looking time, each and very second of the video was very helpful woowwww🤯🤖🤝

[@souravsamant]

Just completed this lecture, once again great explanation.

[@nashville455]

Thanks @KunalKushwaha I am really amazed by the way how you taught all of these. For the reverse number question before seeing the solution i write the below which was completely different from the way you solved it. This gave me confidence and proved that your course made a impact on my thinking abilities There is literally no need to run behind paid courses,when we have people like kunal putting their efforts to make all of this. I highly appreciate the time and dedication kunal showed just to educate. Huge respect static int reverseMe2(int n, int reverseNumber) { if (n == 0) { return reverseNumber; } int remainder = n % 10; // getting last digit of current reverseNumber = reverseNumber * 10 + remainder; return reverseMe2(n / 10, reverseNumber); }

[@codeman0017]

i too write the same way

[@AmanKumar-kc7qp]

Truely ! Kunal bhaiya i was'nt able to solve the recurrsion but through these video i have make my base strong . I completed these video and going to the next video of yours .

[@arnabsengupta8092]

Bro you are really like a magician 😂 ...you are teaching every critical problem just like easy peasy ...within seconds❤love you dada 🙏 love from bengal

[@ALister_priyanshu]

such a great lecture ...man just love your teaching style❤️❤️....also bring the Dynamic Programming lectures soon.......

[@DeepakSingh-bd6mk]

you simply changed my thought process about recursion.

[@m.o.t.a.n.y.a]

Awesome content @KunalKushwaha💯✌️. On the question about reversing a number I came up with a simpler one hope this helps someone out . The method is: Pubic static int reverse (int n){ If (n==0) // base case or stopping condition return 0; else System.out.print(n%10+" "); return reverse (n/10); //Happy coding world!!💛🧡💜💚 }

[@pramodade3935]

Actually, I was thinking of quite the DSA due to recursion. But now I am confidentially saying I am going nowhere. Thank you, man. Love you!

[@Liku108]

Introduction of recursion asa acha tha ki me iss lecture ka sab question khud se solve kardia.thank u kunal

[@KunalKushwaha]

noice

[@jamespeterson7824]

Recursion made really easy 🙂 ..Great explanation in easy to understand manner...good work

[@sbndBhanu546]

57:56 Palindrome using recursion without any other function static boolean palindrome2(int n){//without using any other helper function int len = (int)(Math.log10(n)) + 1; int tenPower = (int)(Math.pow(10,len-1)); int firstNum = (n/tenPower)%10; int lastNum = n%10; if (firstNum != lastNum && len > 1){ return false; } if(len == 1 || (firstNum == lastNum && len == 2)){ return true; } n = n - firstNum*tenPower; return palindrome2(n/10); }

[@pozo-r1x]

lecture is so crazzzy and dammm simpler in the whole world and he looks sooooooo cutee while teaching😁😁🙌🙌

[@shakthim7644]

Can't thank you enough. Your efforts are visible .Extremely thankful to you .

[@divyaraichura1923]

I am so blessed I found you and came to know about how things work, not only like this dsa and java but everything, open source - learn in public- different tech - focus on skills rather than becoming topper in clgs - so on... in 1st year itself Thanks thanks thanks bhai naya shbd banao, sab logoke thanks sunke kantal gaye honge xD