std::unordered_map In C++ | STL C++

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In this video we will learn about std::unordered_map in c++ STL.
NOTES:
0. std::unordered_map is an associative container that contains key-value pairs with unique keys.
1. Search, insertion, and removal have average constant-time complexity.
2. Internally, the elements are organised into buckets.
3. It uses hashing to insert elements into buckets.
4. This allows fast access to individual elements, because after computing the hash of the value it refers to
the exact bucket the element is placed into.
WHY UNORDERED_MAP
0. maintain a collection of uniqe {key:value} pairs with fast insertion and removal.
#dsa #algorithm #cpp #programming #tutorial #competitiveprogramming

[@InariKorusaki]

First time I didn't have to 2x the playback speed. Thanks for keeping it quick and to the point!

[@CppNuts]

You're welcome!! Even i do the same almost all the time for tutorials :D

[@jimmykonings2127]

Thanks for the STL tutorials! Looking forward for the videos on data structures!

[@CppNuts]

Thanks Man.. Just recorded Tree Introduction, now i have to edit it.. :D

[@srinu571]

Please make a video as a last video of STL series and compare all the containers with their complexity for diff operations.. some table format .. like a cheat sheet ;)

[@ronakpatil6081]

i like your teaching style, you teach like mycodeschool channel fashion.😃

[@CppNuts]

Thanks for liking dude.

[@sachin_bhandari8470]

thank you so much ,your videos are very helpful

[@markusbuchholz3518]

As always perfect. Thanks! Do you have plan also to discuss about hash tables ? - I think one of the most beautiful data structure i CS

[@CppNuts]

Thanks.. Yes my planning is to discuss basic DS and then go for advanced DS & Algo analysis..

[@ayushchoubey1686]

I don't know who you are, but you are awesome!

[@badassopenpolling]

In this video you should show how we can store customize key with the basics

[@PuneetKumar-mz9is]

you talked about some hash, Where is that in used in this ?

[@vova-ri2qu]

why are you said that we need calculate hash from value? we need key. not value for hash algorithm

[@trojanhorse8278]

just a small doubt, in unordered map the hashing is applied on key right?

[@CppNuts]

Yes

[@teetanrobotics5363]

Rupesh is on fire.

[@ayansatt1293]

What's the time complexity for searching a key in unordered map?

[@coffeedude]

How do I delete a value from the unsorted map?

[@mansokash2215]

hi, these training codes are available to copy and implement while watching the video?

[@CppNuts]

Check the channels about me page.

[@lazizaakramova8602]

Thank you!

[@wahid4544]

how do you write on screen? what app you use ?

[@surajpokhriyal7761]

why is it printing in reverse order ??

[@PIYUSH-lz1zq]

bro , to iterate over map we use .(dot) and while finding it returns an iterator .... right ??

[@vvpChannel3112]

Could you please create a series on COM component object model ?

[@CppNuts]

I don't have knowledge on this. Sorry..

[@markbenny4643]

Can we change ordered map to unordered map

[@s1mplelance964]

thank u so much

[@CppNuts]

You are most welcome

[@MOHITRANA-to7rf]

umap[1] = 'c' here 1 is what index or element itself??

[@samratpatel8060]

1 is the key using key u can search in map

[@karthickkumar1380]

God You;

[@CppNuts]

Thanks dude..

[@shubhamrangar]

do you want to learn how to hack into system ?

[@CppNuts]

Dude, i can understand the pain.. 😁 I don't know KZbin is giving same add since long time.. And i am frustrated too. But you make me laugh like anything..

[@rohitnegi4651]

Please share the code, it will help us later in revision

[@slappkake2953]

goated

[@PIYUSH-lz1zq]

bro , to iterate over map we use .(dot) and while finding it returns an iterator .... right ??

[@bhupeshpattanaik7150]

This is not c++14 ?

[@theaartslife]

OH YEAHH

[@CppNuts]

Thanks

[@AndersonSilva-dg4mg]

recommend me books about C++ plz

[@CppNuts]

I have never studied book for c++, i can't tell you..

[@c_1947]

What happened at 3:06

[@shivendrayadav5962]

He is saying that if you dont care about order of keys then simply use unordered map rather than map as balancing the map wont have any advantage. thispointer.com/map-vs-unordered_map-when-to-choose-one-over-another/#:~:text=Time%20complexity%20for%20searching%20elements,searching%20is%20O(1).

[@advay6449]

Hello, i found this Video very helpful. Would it be possible for you to upload this "unordered_map.cpp" for us? I was needing to refer and kept having to come to the video. Thanks a lot :)

[@CppNuts]

Please check channel description.

[@advay6449]

@@CppNuts oooh tyvm

[@CppNuts]

You are welcome..

[@useronuralp]

stop interrupting what you're explaining every 20 seconds by advertising your other videos

[@CppNuts]

I won't stop sorry, if you have problem please don't watch. I don't force people to watch, but may be dependent videos so i might have said in video, and it is free content, if you can't listen this much you should never come back to KZbin ever for learning something.

[@useronuralp]

@@CppNuts Sure. But still, if you have to mention a prerequisite video in your some other video like this one, do it once in the beginning and then follow a solid explanation path. You're literally disrespecting the viewer by repeating the same trivial dependency every 20 seconds. Not everyone that use this platform is 9.

[@CppNuts]

Guys please, If you are frustrated then please look for the solution, don't comment on KZbin.

[@crushed_oreos]

@@useronuralp shut up.

[@genericnamethingy]

thank you!