He's the best competitive programmer in my opinion. He devotes so much to the community. Thankyou errichto!

This is the greatest tutorial I have ever seen, soo detailed and crystal clear!!!!!!

This is a work of art and beauty! There are people who can do but can't teach. Then there are those who can maybe teach but can't do. Then there are legends, who can do both at a mediocre level. And then God said, "Let Errichto be". 🙌. You make complex stuff seem so mind-blowingly simple! Can't thank you enough!

The transition from logorithm to constant complexity for each query had put a smile. That was so cool.😎. Excellent explanation. Keep it going.

Finally a video that perfectly explains the core concept. I was able to come up with log n approach before you explained and was so proud of myself. And then you dropped constant time which blew my mind. :D Thanks Errichto!

You are the best competitive programmer. Very thanks. I understood it very clearly. Thanks for spending a lot of time to explain us. Thank you Errichto!

Clear, concise, and perfect explanation

Video quality and explanation is soo good. Thank-you!!

Read about sparse table 2 days back. I checked if you had made any video on it. And here it is. 💯

Amazing tutorial!!! Really enjoyed it and learned a lot!

I don't understand anything you're saying, but your voice is so soothing like ASMR to me

Errichto this is so nice and simple explanation I read it in book but did not understand you are really nice at explaining

I love even more your recent videos

Thanks for this amazing course. Your explanation is just in another level.

that was indeed a really good explanation to sparse tables. Thank you for this video. :)

Keep up these good tutorials. Thanks a lot

I was looking for sparse table tutorial. When I saw Errichto's video in the list, I knew I couldn't get any luckier.

Thank you! Got mine working now! Awesome tutorial!

This is very cool. Eager to learn about the segment tree. I didn't know about this. There surely are good use cases for this algorithm. For sure segment trees, or a similar structure, are used in databases.

He is really great and down to earth person....always willing to do something good for community....👍👍👍

Woah explained so simple, seems like a complex math but it is not once you understand the intent behind thanks a lot for the video

Best Explanation, you made it so easy to understand. Please keep up the good work 😊

c++ also has builtin function __lg for base-2 logs with integers. Nice and clear explanation (as always)!

Thanks ☺️ , this lecture was really helpful.

Finally Errichto is back :)

Thank,I just needed this perfect and Crystal clear explanation .Orz

i love learning from Errichto more than my own profs

Wonderful video. Helped me a lot sir

Amazing stuff, good explanation

Thank you, Errichto.

Very nice explanation Errichto

You never dissappoint!

Dzięki za pomoc w przygotowaniu do Olimpiady Informatycznej Juniorów (:

Great explanation.

Please do some Videos on Data Structure. Your explanations are simple and precise.

today i am practice codeforces Div2 C problem but i am not able to solve efficiently and seen editorial sparse table algorithm is used then learn this from your lecture then simply solve and learn this concept smart way very thankful for you explanation

Amazing tutorial, for so long I was not sure how queries take constant time and not logN time. I always thought we need to answer each queries such that we divide range into powers of 2... finally your tutorial solved that for me that we need to take largest power of 2 which fits in given range and check from L and R end point and hence it is O(1). thank you so much for clearing this :) Also this clears why we can't use sparse table for answering range sum queries in O(1) because we are using overlapping ranges, right?

amazing dude, I've been following your videos for a year now and you are always improving the way u teach. thanks !

He's sooo clever. Thanks for the video

Erichto you are the best person in the world!

may you get all of what you want in life..i respect you

Thank you !

Very nice explanation

Duma rozpiera, że rodak jest takim mózgiem :)

plz do segment tree.. waiting for a long time..

For computing "k" in the query function we can do k=floor(log2(len)) then we can have 2^k

Many thanks!

the best youtuber

What an explanation! op

Amazing👍🏽👍🏽

Wow! its so clear even a 5 year old IQ guy lile me understands , Thank you for the wonderful content Ericchto !

Awesome!!

Thank you

Please make detailed videos on segment tree and it various applications( like, min , max, updating, sum, frequency of max frequent element in the asked range etc...)

The brain on this man

legend.

Won’t the time complexity for answering a single query still logN as we are computing log2(len) where len is R - L + 1 which in worst case is of the order (N). So won’t the time complexity be logN per query?

I agree that using log2(x) is something to be avoided generally, however, if x < 2^31, it is guaranteed that the result of (int)log2(x) will be the same of any the bit tricks, so it might be a good choice if it's faster to code.

You're amazing

This reminds of Reversort in Codejam Quali

Thanks You

Errichto orz ❤️

Nice!! Binary is always Beautiful :)

Hey Errichto, one question, what do you use in order to write your notes, i think you use like a tablet or something

Can we use sparse table for sum queries if we use the method where we convert ranges to binary and add it like we do in binary lifting (query time = logN)?

Should have checked this out before, not knowing sparse tables cost me yesterday as the seg tree failed in time.

❤

I don't know why people disliked this video.🤷‍♂️🤷‍♂️

awesome

Thank you for this great video BTW : Is the __builtin function O(1) or O(log) or what ??

Is the condition in line 30, correct? It does not reflect m[i + (1

Hello guys, I am errichto, is so cool to hear

How do you find problems on SPOJ? It seems so difficult to find by tags.

Can you have multiple overlapping intervals?

Hi , can I know the name of program used to explain pls?

💯💯💯

good !

It would be nice if you covered CSES problemset. It has a lot of educational problems that are hard to solve if you don't know the right technique.

Errichto can you please make a video on how to deal with burnouts we face while constant coding?

please do segment trees next

why it is k

Thanks for this vid - i like your background - so the goal to the get the O(N*log((N) + Q) though N is increasing tremendously ?

pls do video on disjoint set union

We can also solve this problem using sliding window concept in O(n) time

I got WA with this code on spoj, do you guys have any ideas?

Line 27, shouldn't it be i

2 year's in and still waiting for the segment tree video

Can someone explain me what is “1

Easily explained.

It is like segment tree

10:00 this was when I started thinking that sparse tables are clever.

How would we handle updates?

i dnno, this guy is godtier. I cannot compute. syntax error

Please do make how and when u started doing cp. Love your videos from Bangladesh

Segment tree can also do the same right? So whats the advantage here?

your balance bracket concept apply div2 B problem in contest get Accepted and my rank under 2500 thanks for you good job

Hey in preprocessing part inner for loop should be for(i=0;i+(1

I can AC the cses problem but cant for the spoj :))

I saw this somewhere to find largest power of 2 less than or equal to n: x=n While(x&(x-1)) x&=x-1; Now x will be the answer

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