After a year hiatus (sorry, got busy with work!) this series is continuing! Check the next video out here: kzfaq.info/get/bejne/bc2HebVylbyUf3k.html

Great stuff! Super underrated channel (but not for long i bet =) )

After 4 days of struggling, this video finally gave me the breakthrough to understand hash maps in my self taught journey. Concise and coherent, this is the best tutorial video I've seen so far!

Not even half way through this video and I just want to give props to how concise the information is. I hope to see some machine learning content soon :)

this is first video, but i'm already excitement about learn next algoritm in this series. The best.

Brother I literally saw 8 videos about hashmap and was always getting confused at one part or the other. Your video literally is a goldmine. Thanks for adding an example problem helps a lot!

I am just starting to study DSA by myself and this video was EXACTLY what I needed. You explained it so well that I thought the leetcode problem was EASY. Great video!!!!!

I love the fact you go through an actual problem at the end. That made it “click” for me. New sub here, please keep it coming!

Great video. It’s hard to strike the balance between keeping things concise while also exploring them fully, but you did an incredible job of it here.

I watched this video like 3 times over a month ago, and I was struggling with understanding the logic even though you tried so hard to explain it. Now, after some practice, I watched this video once again and I can say I understand the code perfectly now. I just wrote the code before seeing the solution. Thank you for yours videos, one of the best channels out there!

Great video. After I watched your video, I tried to code it myself without looking and tried to do it without defaultdict(), just adding my first val as a list and then appending to the list for the following ones. After I had done that, I converted it to be like yours. Besides the obvious benefits, something else I realized was doing it your way removed the need to check if a key was already in the dictionary. In my version, I had to make that check, otherwise, I would be attempting to append to a list that hadn't been created yet.

great hash map explaination, plus it have leetcode example and explaination for the answer in detail at the end of the video which is really great.

Underrated quality channel , note:- [add more interaction in video(llike use pencil or notepad for raw explain ), cause people like interaction.]

This is what should be ranked #1 when searching for "python hashmap"

The explanation on this was so clear. Absolutely brilliant. You have gained a new subscriber and I can't wait to see this channel grow the way it deserves to!

city_map = {} cities = ["Calgary", "Vancouver","Toronto"] city_map["Canada"]= cities # This works so much better

Seriously man, i could see your hard work through this video.

This was a really amazing learning video, I like your style of teaching that first of all you made the concept clear and then a question to make it more clear. Btw I was here because I didn't get clarity with the neetcode channel of the same question. so I request you to upload these types of videos more thanks 🙏

So, ive been programming in python for a little over a year, and i've always seen those hashmap memes, and how they're the solution to everything, but the name Hashmap just seems intimidating, so i never bothered thinking about using one or looking up what it is...until this day, when i realized its just a dictionary, and I've been using them all the time lol Great video, keep it up!

The video was great! However, if you use the SORT method, the best time complexity you would get is O(nlogn). If you want to solve it in O(n), a clever approach is to first check every word and create a key value pair of every letter. For example, you go through the first word and get 3 'a', 2 't' and 4 'e'. Now you save this in a dict { 'a':3,' t':2, 'e':4 }. Then, you go through every other word and do the same. If you find any other word with 3 'a', 2 't' and 4 'e', you have found an anagram. So just comparing the dicts at the end would give you the anagrams. You would go through the list only once so you have time complexity O(n). P.S. you should first check if two words are the same length. If not, you can automatically cancel them as anagrams.

hey bro thank you so much don't focus on views just post and you'll make historical content as your vids are easy to understand because of the analogies you use thank you so much buddy lots of love from india

A+ instruction video. Clear and concise. Just subscribed.

Your explanation is simply the best one I found, thank you so much man!

The best explanation I found about this topic yet! Thank you so much, God bless you

Please complete this playlist, its really helpful. Btw i just subscribed so keep up the work please.

Please make videos often , stuff is great and smooth

wow, still wrapping my head, I am new to it, but its very concise and all good content, man.

IMO, best explanation on YT

Next video of this series? I need it badly for learning DSA from scratch...

That's incredible, I understand it right now. Thanks you, it really simple explaination and easy to understand

great content and will continue to watch in the future :)

Wow. It makes sense now. It finally makes sense. Thank you!

Goat vid codebagel, do more implementation vids!!!

Great Work! Nice Explanation Dude. Really helpful

Great explanation

great video :)

This is awesome! thank you very much for making this video!

ngl ur actaully a good teacher

Thanks! You really help me! Wish you 1m subs and more

sir instead of using we can use return anagram_map.values() this will be more efficiant

Lovely Vid!! Great Work

Let me start off saying i really appreciate the content. It really filled in a gap in my own understanding in how i can use hashmaps. Question, correct me if I'm wrong please, I'm still learning code and computer science in general, but if the key is being transformed by a hash function, which to my knowledge, doesn’t care what order the input is, meaning it will give the same hash value and map to the same array index regardless of the order, do we need to sort it at all? I guess in terms of readability it helps, i guess im just am looking at the fact there is an additional operation being performed to sort the characters into a new list. I know it wont affect performance significantly in a example where there are three characters being sorted and im being a little weird like "what if i had a list of regular expressions?" or something where the data can be arbitrarily long. Also, would that eliminate the need to cast the result of sorted_s as a tuple? I dont know if python under the hood treats strings as a list or something else. If it does, wouldnt that also eliminate another operation. Again, i want to thank you for your time and effort and its great content for sure and it helped me learn more about something im deeply passionate about. Just want clarification if im misunderstanding something.

Your content is way better than any paid one ,but you seriously need to do marketing ,make some content related to india and your channel will get some instant boost , make a video on "Top 10 common python algorithms asked by Maang in India" ,btw love from India

Hey codebagel i request you to please upload complete dsa playlist using c++ and loved your amazing content

Man, this channel only have 19 videos at this time. I wish you could do more about algorithms and data structure.

underrated

But isn't sorting each of the strings inside the loop making the time complexity O(n * nlogn)?

You're great, good explanations

Great job! thanks for your video

Appreciate the video, well explained 👍

for the results, you could just use result = list(anagram_map.values()) correct me if this is not the correct way. tq

Guddhabagala cheppinaw❤❤❤

How are hash maps faster if they are built on top of arrays and use index to find the value?

Great Explanation you should make more videos

On timeline 5:33, you initialized city_map with list, can you add other data structures such as tuple in it? Am new to python, I hope my question makes sense

I have a question about sort(). From what Ive read, using sort() runs at O(nlog(n)), is this still the case for using it on a string even though strings are limited to a small number of letters? Thanks in advance!

I don’t think you can use import for the most of the interviews

dude like wtf, dthe moment you said city_map = dict() i was like wtf, i've be working with hashmaps for the past 6 months and i had no clue

Excellent!!

Hello, thanks for a great video! Can you also please explain if Hash Tables and Hash Maps are the same (in general) ? If different, how does python dictionary Data structure handle them? thanks so much in advance !

Awesome, keep it up

Damn, that's a very good video ...

I didn't understand the part where the strings got assigned to the respective key automatically. How did that happen? Is it the work of defaultdict?

bro do more vids about all dsa pls , this vid is really good

sorting has its time complexity right, how is this optimal? who decides that?

Bro why didnt you continued this series 😢 plz tell us if u moved to another channel we need you

where did you created the module collection

can we use long long type and do bit-masking?

Simply Wow - from a noob!!

Thank you so much!

Can I just return anagram_map.values() instead of the result list? I'm not sure if there's some kind of issue later on but is it faster to do it by returning values since it is already in list form rather than adding 1 more for loop?

nice job keep going =)

using the equal sign to denote a key -> value connection is not a good choice imo

love this video!!!!!

how simple, i didn't it was this simple to think. Find two numbers which gives the sum 10 from a list of number lets says [ 1, -3, 4, 6 , 9 ]. So here I would say for 1 the number is 9, -3 its 13 so on. So essentially I created a dictionary (hash map) with key as the result of 10-1, so when I want to check for the next number is the one, i can just check arr[9] and if its present then I have the first solution. Damn.. To make it even more simple, you take your question process it for every element in the array in a way that the dictionary benifits from the result you generate. Ig thats hashmap, its just making dictionary. In that logic an array is a hashmap where the key is already defined. so its O(1) from start, but for hashmaps sinse you need to check every element to create a hashmap the the program is O(n) or more as it depends on question but once the hashmap is created the order its exec is O(1)

Great channel

For the result you should have just called .values no?

thanks WholeHeartedLy !!

thank you

Are hash maps and hash tables really the same?

why do another for loop why not just return anagram_map.values() ? it already returns a list and the values are in a list so its already a list of lists

the best ....

Amazing Man, you and @Neetcode are the best channels for learning python

wao wao wao

Dude, you have used sorted inside a loop, isn't it increases a time complexity.. Here, you are claiming O(n) but i think its greater than that because sorting function of python also taking some time complexity based on "n".

list comprehension

And I had to search in Japanese to find the video, even better.

Without the defaultdict is a bit more complex to solve :`)

Please dsa in cpp

Dammm🎉

you make good coffee wao wao wao wao

Kinda felt happy to see Pakistan in the example, i don't know why😂

Why the funny names in programming? This always happens whenever I try to resolve a problem. Why can't they just say it how it is ? I was intimidating hearing a crazy word like HashMaps only to find out I've been using them the whole time, dictionaries. Same goes for relational databases. I've been using them the whole time but because I didn't know what the interviewer meant by relational, I messed it up and she gave me an eyeball like I was a fraud. I still remember the "oooOOk Kaaaay". Just say , "you know the database with manytomanyfield or onetoonefield?" instead of these nonsensical words. Talk practical not theory. Idiots.. Sorry for the rant, it's just these funny names can trip up people.

**Keep uploading more LeetCode, NeetCode, DataStructures and Algos. cities = ["Calgary", "Vancouver", "Toronto"] city_map = {"Canada":[]} city_map.update({"Canada":cities}) print(city_map) ============================ from collections import defaultdict class Anagram: def group_anagrams(self, strs): anagram_map = defaultdict(list) for s in strs: anagram_map[tuple(sorted(s))].append(s) return list(anagram_map.values()) anagrams = Anagram() print(anagrams.group_anagrams(["eat", "tea", "tan", "ate", "nat", "bat"]))

why did such a small code at the end take such a long time for me to understand

You're amazing thank you so much 😭🩷