One time I decided to learn Python. I bought books, registered for a class at a local university. After 2 classes I realized I already knew python. Because Python is just C++ for kids. And I have the maturity of a 7 year old.
1) IO operations take about, I dunno, like 1000 times as long as most other instructions, and are completely done by the OS. Which means that IF you managed to write the same code in both languages, you would get basically the same speed. 2) However you did not write the same code, the Python program (probably) reads larger chunks of the file at a time, and since reading 1 byte and reading 4kB takes approximately the same amount of time, it obviously takes less time 3) You are using completely different data structures. In Your Python program, you are using IMMUTABLE STRINGS, so they can safely avoid copying, and instead just reference the input data, while your C++ strings are MUTABLE, so they (likely) have to copy the data
To add to Point 1, IO operations are slow cause, if i remember correctly, they don’t include buffering so the program have to fetch data from the main memory instead of using a cache
@@pixelitedragon1720 is it? I think cache useage is transparent to all programs (OS included) (programs can't choose whether to use main memory or cache)
No, they might grow resistant to it. Show them MY code Also, you can make them learn python, while simultaneously not dropping C++. Then, make them write a program (without compiling it and without copying from other sources) in python and in 10 minutes(after start) make them write the same one in C++(also without compiling it and without copying from other sources). Repeat until they're done. After that, compile both programs. Profit
Now the good part: in C++ you can improve the code so it runs much faster. In python you can do not much to improve unless you write a wrapper which calls C++.
Well actually you CAN improve interpreted languages perfomance a lot. In any algo there are optimizable bottlenecks. The difference is that you can push optimization farther if you are using language with memory control
@@janisir4529 nono, u misunderstand. it is a refernce with a comparison between c and c++ :D if u fuck up memory management in c u can shoot urself in the foot in C but in C++ u probably blow your entire leg off if something goes wrong :D
@@dysrhythmic percentage points is a thing but it doesn't apply in this context; it only applies when the values being compared are themselves percentages
C++ cin and cout streams are very slow by default because they have to wait and sync with the C standard streams. Add std::ios_base::sync_with_stdio(false); and run the test again
@@knowledgenews5343 there's a whole stack overflow page about the issues with it and I just think typing std:: before everything is a good habit anyway
you can't scare a c++ deeloper dude, in python you've read the whole chunk at once, but in case of C++ you're reading it line by line --- causing more input operations resulting in more time, in fact i'm impressed that c++ takes this less time for a million input operations more than python.
Yes, sys.stdin is buffered. The iterator iterates over the internal buffer line by line. The assignment does not have any effect. The bytecode-compiler will remove this line. If you want to test the speed of the languages, then you have to take IO away. Both tests require the same conditions, and it's not the case with the example code.
It has more flexibility with {} and ; Also you do not need the right amount of SPACES.. yes right SPACES! not TABS! It has to compile and tells you about lang mistakes before running program not in the middle of running. And I forgot. You define type of variable so you know what it is. In python you come bck to large old code and have no idea what type a variable is cD
Python will often use a single memread to open and contain files, which allows for a speed-use of large files, but C++ would not optimize that unless specifically instructed! Fun video, thanks!
@@andrewwhiteman8892 Sure! In C++ the code is "memtemplate" or "memcpy", which are implemented through a memset operation in C-lib. All code in the C-lib environment is pretty outdated, but you can create a similar function in this way: global ptr* load-file func { # pseudo-code for loading a file from disk into memory, using chunks aligned with page and disk-block size findChunkSize(useCurrentDisk is true) store in localVar ChunkSize; # this needs to find the largest, common size that fits in both one page size, which is how many bytes are loaded by the operating system for a single-use, and one block size, which is how many bytes are read by the hard-disk in a single read operation readOneChunk(useSingleChunkIO is true) store in localVar SingleChunk; # would need the block-place of the file in question, as well as localVar ChunkSize, etc, which are often omitted in pseudo-code, as it is a guide only, but I thought to mention as I would write it in! ConfirmChunkIsRead() returns true or false, test; # sometimes the disk is too busy to read and will fail, etc. By pseudo-code rules, no exception handling is needed, but here would be one UseSingleChunkFollowOn(pass-in SingleChunk, useDigitalSideIO is true) store in localVarArray AllChunksOfFile; # the SingleChunk is already measured, and includes where it was found for easy read-on-- DigitalSideIO is a boolean true or false for whether to follow the chunks as an abstract "file" (which We want) or literally as blocks on disk (for simpler I/O) # all chunks are read, and now are stored for access outside of the same-func. UseGlobalAlloc(sizeof AllChunksOfFile, cache-memread pass-in AllChunksOfFile) as return } Python uses a smaller form of this same function to cache exactly 1 MB or so. The later versions of Python will attack the file in different ways to further improve system-side caching without having to test if there is a large memread cache on disk, in the operating system, or other ways. All of this code is in Python's "memread" and "system IO call-func" parts, in case you're further interested. Take care!
@@computerscience3836 You sound like my college professor. He refuses to teach anything but Fortran 77 (in 2024). He doesn't understand that different languages have its places. Why the hell would I create a plot in C++ when I can scratch together a notebook and do it faster in matplotlib? Every language has its place. (except Java).
@szymonzak5968It's literally basic stuff. This ain't nerd level. Even the 193/128 * 100 = 150% is basically just saying 50% more than 100%, a 50% increase. Ie, 50% faster. Get your nerd emoji out of here.
The fact that a python programmer would think using I/O to test code performance is something reasonable, is exactly why this video makes the opposite point it's trying to.
Haha good one. This is why python has been traditionally used for embedded, realtime, OS, games, heavy desktop apps, and writing other major tools and runtimes...oh wait
python is slow tortoise ; when it becomes larger your program becomes slow as tortoise ; maybe this dude has 256 gb ram and that's why python is fast ; go and test it in the slow pc with 2 or 4 gb ram and you will see
@@Phantom-lr6cs fun fact: you said to test it in a slow pc with 2 or 4gb ram, so you just pushed the blame on depending on how fast the pc is, also dude doesnt have 256gb no one has 256gb ram plugged to one pc
hot take: if you really wanna scare c++ programmes, you should ask them to use std::find on an array of some structs and then try to read the compile error, lmao.
Testing LANGUAGES speed by calling functions handled by OPERSTING SYSTEM is like comparing milk quality by comparing their price - may look connected, but sometimes can fool you
As someone who is a c++ programmer who also does a bit of python occasionally, sure, as others have pointed out, there's ways of making the c++ version much faster. But unless I really needed the optimization, for something simple like this, I'd probably use python.
How do you start as a programmer and what should be learnt to pass as a programmer myself? I only know std::cout, struggling with std::cin, and thought namespace is useless.
@@Raspredval1337 you think so? Do you mind explaining why is that the case (I think C++ is way harder, the amount of syntax and features are just insane)?
@@Raspredval1337 yeah especially when you should be doing c in another few more lifetimes, but that lifetime lifespan you're having is 50+ years < my lifetime lifespan of 2 lifetimes Xd
@@davidwuhrer6704 One can use Pycharm and pygame. But it'll be much harder since most game engines use C#. So, you've to do it without Advanced features which increase the difficulty level tremendously.
@@Sumirevins Akshually scripting in python does not sacrifice any features, quite the opposite, it makes them more accessible and adds new ones. Nor is scripting in python more difficult that writing C#. One of the major selling points of python is how easy it is to write something readable in it. And most game engines are written in C++. Only Microsofties use C#.
The reason here is that Python doesn't read and write the line into a string, it's only reading the new line characters from the stack and counting. C++ is reading and writing every line into the heap, this is vastly different and therefore the reason it runs slower.
@@aaarkidI just tried this code and the perfomance is worse than the one in the video, the best method I found was to read the file with fstream, it became insanely faster, and when we read the whole file with Python its performance keeps the same
i have done alot of coding in both cpp and python, and honestly, cpp feels alot more comfortable. one of my friends said this : "when i code in cpp, it feels like i m coding, but in python, it feels like writing english."
-O3 enables some aggressive optimisations and TRIES to vectorize it, but, since the user didn't specify the vectorization options available to the compiler, it didn't vectorize it. Just pass -msse or -mavx to the compiler and you'd see the difference. Plus std::iostreams are kinda slow, should've used the cstdio primitives.
It might be purely because iostrams are slow. I looked at the disassembly of some C code i wrote that is of the same function but uses read() directly, it did actually vectorize something - it doubled the instruction count and there is vector register manipulation everywhere, but this had almost no effect on performance compared to an unoptimized version; however both were as fast as python, as a speed about twice that of the optimized C++ version. i would assume the same happens to the C++ code if you remove iostreams, although i did not examine that for some reason.
C++ streams are slow because they are forced to wait to sync with C's stdio by default. There's a parameter in std::ios_base that you can change to disable sync with C stdio which makes C++'s streams much faster. Obviously they are still slower than raw stdio because streams internally make a bunch of checks to convert the data that you're inputting/outputting to and from the streams.
@@AlFredo-sx2yy just paste std::cin.tie(0); std::cout.tie(0); std::io_base::sync_with_stdio(false); before doing any IO and cin and cout should be same speed as scanf and printf (iirc cin and cout are even faster than scanf and prinf with this)
It's because there is a mutex to have thread safety with cin and cout in c++. You can disable it. And Python is monothreaded so there is no mutex needed.
By the time python reads the input buffered in memory, C++ has done 700 000 stdin read calls of arbitrary length. It's like reaching for a shelf in the same room and walking a few blocks to get a book.
it's probably because sys module is implemented with cpython, so you're essentially comparing c against c++ otherwise looping in python is extremely slow
C++ IO is slow by default because C++ streams are programmed to sync with C's IO. There's a parameter in std::ios_base that you can use to disable that sync and that would make any IO operation in C++ much faster.
I've done this by accident when working on college project, my nerd friend lost his shit when he saw my absolute disaster of a code I've created. He literally screamed "NO WHAT ARE YOU DOING?!?"
@@thelemoid not even that, the fact alone that a std::string is being used is enough for me to be annoyed at this. std::string classes are mutable, while the strings in python are immutable (reminder that python is backed by c). trying to argue that python is faster than c++ while not even using the same data types. after rewriting the C++ code to read into a char buffer, i get pretty much the exact same time as python (which is exactly to be expected since python is also just doing c stuff under the hood) if i rewrite to use buffered input, i could definitely improve the speed by a lot more but im lazy right now lmao
Fun video. Nothing against some lang-rage-bait every now and again. Would have been interesting if you had a second part (or separate video) where you dug deeper and understood the reason the result was what it was. Look deeper into Pythons file implementation for example (since I take it you probably prefer digging there rather than in C++'s std).
Haha nice one. Well on a serious note this is just simple print operation and a counter. When writing more complex things Python provides libraries which are generally slower than C++. If you implement the same thing in Python yourself you can get equal speed etc. But Python is preferred because of its easy syntax and support of a LOT of libraries which allow you to do anything rather than implementing them. (C++ have as well, but Python has more)
Python isn't that much different from C++ in some ways. I have learned some Swift, C,C++, Rust, Python, Nim and probably more from the C/C++ family of language as well as several more from other families of languages. All the languages from the "C/Algol family" are much the same. They are all imperative languages with a similar syntax. Languages like Haskell and Prolog are totally different, they don't feel like your programming in the same way and you need to convert the programs from an imperative train of thought to a declarative logic. The biggest difference between Python and C++ is that Python is interpreted and doesn't have the duality of compile time vs runtime. I cannot comprehend how people can use dynamic languages for big projects, I get nervous just thinking about it. Python is great for engineers and data scientist and using jupyter notebook is an incredible tool where you can do things in a way that maybe wasn't feasible before. But actually creating application software in it sounds almost irresponsible unless your writing millions of unit tests(and some do).
depends on the project... python developers are cheaper, also it IS quicker to build something in python... then, it is also possible to design things wrong - and for c++ that could be costlier... no programming language prevents errors from happening, in C++ they can be harder to diagnose and fix than in python
my benchmarks: py3: ~0.490 c++: ~0.800 I/O operations are very long, that does not depend on the language, and the times should thus be about the same. However python has I/O code more optimized than this C program written in 5 seconds, using less I/O operations thus the faster time. Optimizinf the C++ code by ditching C++ because i can’t write it, and rewriting it in C reading chunks of 2048, i can get it down to 0.465, which beats python ever so slightly, probably due to load times or something.
That's the shitty part about C++. Reading file line by line is very common idea. To do it efficiently you need to do lots of steps. In fact in C++ I avoid them entirely and read whole file. And only ~5 years ago c++ got normal api for telling file sizes. No, rewiding file to the end, using tellg, rewinding to beginning is not normal.
@@ItsCOMMANDer_ That could be faster, but memory allocations are quite fast on modern systems, and by doing that you lose the ability to re-use the code for reading from files on unknown length. It, as almost always, depends on context
@@chri-k you can do something like a function, wich takes an FILE object, uses fseek to go to the end of the file, say at what character it is (e.G. 25 charcater is theast so the contwnt of the file is 25 bytes. (not including \0 ) long and then just allocatge memory for that amount and use fread to read the entire file.
Delusional. Practically all abstraction except polymorphism are resolved at compile time. C has a very clean and understandable look but C++ is more powerful, it's just the truth. Try benching any code.
@@torshepherd9334 templates are such a nice convenience when it comes to writing code, but a major pain in the rear when it comes to reading it as an outsider. I'd rather not touch those things beyond aliasing composite types, and maybe one or two inliners.
The thing that scares me about python is not so much the performance (not everything needs to be lightning fast), but rather the lack of curly braces and static typing which can easily get messy and confusing if you're not careful
The problem are IO operations which are not meant to be used on production by any means. In any real C++ application (Most probably a multimedia system) console outs and console ins are a big no no. In audio programming for example, there is a constant loop through really small slices which together makes frequencies and therefore sound. In the loop you should never use a cout or cin for debugging because it will damage completely the audio output.
I love both languages. Python bc it's easy to make a project, and C++ bc I feel like a pro programmer when programming in it. But Im seeing that the purpose of this video actually worked, there are so many C++ devs scared in comments. Including me
To solve this riddle: Ptyhon has many library functions that are natively coded in C and quite optimized (using low level system calls and stuff) As long as you use those packages, you will probably beat most languages (because C is very fast, if optimized)
Python programmers : Thanks 🥲🥲 C programmers : Outside : Scary?! Us?! 😂 Yt comment : Write whole c history to prove they are not scary Java programmers : You guys even write code to write 1 million lines. It is more easy for us to write those 1 million lines.
For me, the weird thing is that it's a bit complicated and hard for me to know python but for some reason I understand c++.. I don't know why but that just happened Although I actually managed to make turtle python art only circles and lines but in C++ basically just made my custom header file so instead using cout, I use print.. (I like to see the world burn slowly and painfully)
I did a C++ program that simulate the result of throwing a dice 10 million times. Then, I did the same algorithm in Python. C++ did it in like 0,5 secs, while Python lasted a few seconds.
One time I decided to learn Python. I bought books, registered for a class at a local university. After 2 classes I realized I already knew python. Because Python is just C++ for kids. And I have the maturity of a 7 year old.
@@HuntingKingYT Holy shit. No cap?
@@Thisguy12345-m Hi, i'm the guy who asked, enjoy :)
@@Thisguy12345-m I also, indeed, asked
Python is not for kids
@@Thisguy12345-m he's contributing to the conversation dumbass
1) IO operations take about, I dunno, like 1000 times as long as most other instructions, and are completely done by the OS. Which means that IF you managed to write the same code in both languages, you would get basically the same speed.
2) However you did not write the same code, the Python program (probably) reads larger chunks of the file at a time, and since reading 1 byte and reading 4kB takes approximately the same amount of time, it obviously takes less time
3) You are using completely different data structures. In Your Python program, you are using IMMUTABLE STRINGS, so they can safely avoid copying, and instead just reference the input data, while your C++ strings are MUTABLE, so they (likely) have to copy the data
To add to Point 1, IO operations are slow cause, if i remember correctly, they don’t include buffering so the program have to fetch data from the main memory instead of using a cache
god bless you bro, was actually gonna go insane for a moment because thats literally not possible
Thanksssss. Other hours of study, do have you got any advice to learn these small details?
@@carlomaggiolo2180 1+
@@pixelitedragon1720 is it? I think cache useage is transparent to all programs (OS included)
(programs can't choose whether to use main memory or cache)
How do you scare a C++ programmer? Show them their own code
Show them Asssembly code!👾
@@spicychad55 show them INTERCAL!
No, they might grow resistant to it. Show them MY code
Also, you can make them learn python, while simultaneously not dropping C++. Then, make them write a program (without compiling it and without copying from other sources) in python and in 10 minutes(after start) make them write the same one in C++(also without compiling it and without copying from other sources). Repeat until they're done. After that, compile both programs. Profit
And say there's 1 mistake there, but don't tell them what it is.....
For some reason that reminds me of the punisher meme of him screaming “WAIT WAIT WAIT” while sobbing
Now the good part: in C++ you can improve the code so it runs much faster. In python you can do not much to improve unless you write a wrapper which calls C++.
Well actually you CAN improve interpreted languages perfomance a lot. In any algo there are optimizable bottlenecks. The difference is that you can push optimization farther if you are using language with memory control
@@soanvig for loops in python moment (don't tell me about map() )
You can improve the code written in python.
Write it in C++
@@soanvig And the fastest you can take python is by calling a c++ code anyway.
@@sid6415 I believe its c not c++
How to scare Python developers:
POINTERS
I thought C++ programmers can't be scared, they already live in an eternal fear
C++ is great once you learned the million most common way to foot gun yourself.
@@janisir4529 Correction, not "foot gun"! Blowing your leg off.
@@annorome It's technically "shoot yourself in the foot" but I prefer it my way.
@@janisir4529 nono, u misunderstand. it is a refernce with a comparison between c and c++ :D if u fuck up memory management in c u can shoot urself in the foot in C but in C++ u probably blow your entire leg off if something goes wrong :D
@@annorome What? The most likely outcome in both cases is an access violation crash.
This is why C++ is reserved for people who know what they are doing :D
I have no idea what I'm doing... ....and I'm currently using STM32 ARM C
@@cpK054L currently writing Borland C for DOS
i want to know :o(
@@ownedbyptr Ah... those were the days.
Truth!
It would actually mean it’s 33% slower. 150% is a 50% increase, but going back down is only a 33% decrease
It's 50 percent points slower
@@gwch3481 that makes no sense "50 percent points" doesn't exitst
@@goutgueule9197 google percentage points right now then come back here and apologize to the guy
@@dysrhythmic percentage points is a thing but it doesn't apply in this context; it only applies when the values being compared are themselves percentages
@@dysrhythmic ok ok sorry but i had never heard of that and to me it made no sense
C++ cin and cout streams are very slow by default because they have to wait and sync with the C standard streams. Add std::ios_base::sync_with_stdio(false); and run the test again
Or just learn lua instead of using either of these shitcodes
@@monologicaly you can't really compare the two, they have entirely different use cases
Not ios_base::sync_with_stdio(false); ?
With 'std', yep
@@deathbell616 yeah sorry, it's std::ios_base
using namespace std was the scariest part
My teacher in school tells us to use 'using namespace std' and it's scary af
Why?
@@knowledgenews5343 there's a whole stack overflow page about the issues with it and I just think typing std:: before everything is a good habit anyway
@@knowledgenews5343Basically it pollutes the global namespace with std functions which potentially could cause function name collisions.
That told us everything we needed to know, didn't it?
you can't scare a c++ deeloper dude,
in python you've read the whole chunk at once, but in case of C++ you're reading it line by line --- causing more input operations resulting in more time, in fact i'm impressed that c++ takes this less time for a million input operations more than python.
When the comparison is fair:
ua-cam.com/video/VioxsWYzoJk/v-deo.html
Yes, sys.stdin is buffered. The iterator iterates over the internal buffer line by line. The assignment does not have any effect. The bytecode-compiler will remove this line. If you want to test the speed of the languages, then you have to take IO away. Both tests require the same conditions, and it's not the case with the example code.
oo lemme try!
java
Just be honest...
For me, C++ still comfortable than python. Don't know why, but by putting "{ }" feels.... AESTHETIC
i thought i am the only one that feels the same about c/c++ vs python lol
I will remain unhappy with significant whitespace. it makes sense but is also evil
For me not realy that {} feels good, but pythons way of handling that with indentation feels absolutely horrendous
It has more flexibility with {} and ;
Also you do not need the right amount of SPACES.. yes right SPACES! not TABS!
It has to compile and tells you about lang mistakes before running program not in the middle of running.
And I forgot. You define type of variable so you know what it is. In python you come bck to large old code and have no idea what type a variable is cD
That’s one of the major reasons I hate Python, the code looks broken to me without brackets coming from C
Python will often use a single memread to open and contain files, which allows for a speed-use of large files, but C++ would not optimize that unless specifically instructed! Fun video, thanks!
Then what's the optimized code? Can you show me?
@@andrewwhiteman8892 Sure! In C++ the code is "memtemplate" or "memcpy", which are implemented through a memset operation in C-lib. All code in the C-lib environment is pretty outdated, but you can create a similar function in this way:
global ptr* load-file func {
# pseudo-code for loading a file from disk into memory, using chunks aligned with page and disk-block size
findChunkSize(useCurrentDisk is true) store in localVar ChunkSize; # this needs to find the largest, common size that fits in both one page size, which is how many bytes are loaded by the operating system for a single-use, and one block size, which is how many bytes are read by the hard-disk in a single read operation
readOneChunk(useSingleChunkIO is true) store in localVar SingleChunk; # would need the block-place of the file in question, as well as localVar ChunkSize, etc, which are often omitted in pseudo-code, as it is a guide only, but I thought to mention as I would write it in!
ConfirmChunkIsRead() returns true or false, test; # sometimes the disk is too busy to read and will fail, etc. By pseudo-code rules, no exception handling is needed, but here would be one
UseSingleChunkFollowOn(pass-in SingleChunk, useDigitalSideIO is true) store in localVarArray AllChunksOfFile; # the SingleChunk is already measured, and includes where it was found for easy read-on-- DigitalSideIO is a boolean true or false for whether to follow the chunks as an abstract "file" (which We want) or literally as blocks on disk (for simpler I/O)
# all chunks are read, and now are stored for access outside of the same-func.
UseGlobalAlloc(sizeof AllChunksOfFile, cache-memread pass-in AllChunksOfFile) as return
}
Python uses a smaller form of this same function to cache exactly 1 MB or so. The later versions of Python will attack the file in different ways to further improve system-side caching without having to test if there is a large memread cache on disk, in the operating system, or other ways. All of this code is in Python's "memread" and "system IO call-func" parts, in case you're further interested. Take care!
bruhh what the fck is this
@@ChrisContin
Even just removing sync io with stdio makes it much faster than python.
You mean like mmap?
So true, it scares me how lacking Python programmers seem to be at designing benchmarks.
print("0.138 s")
Python programmer is a bit of a stretch. Python is about a half step up from Scratch. It is a toy language.
Python programmers are bad at designing anything.
@@computerscience3836 You're a toy programmer if you don't recognize that different tools have different use cases lmao
@@computerscience3836 You sound like my college professor. He refuses to teach anything but Fortran 77 (in 2024). He doesn't understand that different languages have its places. Why the hell would I create a plot in C++ when I can scratch together a notebook and do it faster in matplotlib? Every language has its place. (except Java).
You compared buffered I/O in Python to direct I/O in C++.
Holy fucking shit the misspelling at the end made me laugh way too hard.
Actually, based on your questionable figures, it's 33% slower. Or you could say Python is 50% faster. You need to work on your math skills.
🤓
@szymonzak5968It's literally basic stuff. This ain't nerd level. Even the 193/128 * 100 = 150% is basically just saying 50% more than 100%, a 50% increase. Ie, 50% faster. Get your nerd emoji out of here.
The fact that a python programmer would think using I/O to test code performance is something reasonable, is exactly why this video makes the opposite point it's trying to.
Man this video is a joke
The fact that you couldn't see that this is obviously a joke, is exactly why the video makes the point it's trying to.
And I/O operation with different data structures too
class TrisT: public Butthurt {}
I was affrendered, as a letter C.
01:10 - "learn phtyon". ok.
Haha good one. This is why python has been traditionally used for embedded, realtime, OS, games, heavy desktop apps, and writing other major tools and runtimes...oh wait
python is slow tortoise ; when it becomes larger your program becomes slow as tortoise ; maybe this dude has 256 gb ram and that's why python is fast ; go and test it in the slow pc with 2 or 4 gb ram and you will see
@@Phantom-lr6cs fun fact: you said to test it in a slow pc with 2 or 4gb ram, so you just pushed the blame on depending on how fast the pc is, also dude doesnt have 256gb no one has 256gb ram plugged to one pc
just to be replaced by a Java developer 🤷🏽♂️
@@Phantom-lr6cs Windows user detected.
More RAM doesn't make your programmes run faster, unless your OS is constantly thrashing.
@@Phantom-lr6cs the only thing RAM would be affected by...is the bus speed....and even then it barely matters if your COU bottlenecks it
hot take: if you really wanna scare c++ programmes, you should ask them to use std::find on an array of some structs and then try to read the compile error, lmao.
can you write the compile error here ?
@@elia0162 here it is:
Executing task: /usr/bin/g++ -fdiagnostics-color=always -O3 -mavx /home/***/Projects/cpp/testing/source/*.cpp -o /home/***/Projects/cpp/testing/bin/release/out -Wall -Wextra -Wconversion -Wpedantic -Werror -std=c++20 -lfmt
/home/***/Projects/cpp/testing/source/main.cpp: В функции «int main()»:
/home/***/Projects/cpp/testing/source/main.cpp:289:22: ошибка: не найден метод для преобразования в «(const std::ranges::__find_fn) (main()::Test [50], main()::Test)»
289 | std::ranges::find(lpTest, Test{5, 7});
| ~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~
In file included from /usr/include/c++/12.2.0/ranges:47,
from /home/***/Projects/cpp/testing/source/main.cpp:3:
/usr/include/c++/12.2.0/bits/ranges_util.h:445:7: замечание: candidate: «template requires (input_iterator) && (sentinel_for) && (indirect_binary_predicate) constexpr _Iter std::ranges::__find_fn::operator()(_Iter, _Sent, const _Tp&, _Proj) const»
445 | operator()(_Iter __first, _Sent __last,
| ^~~~~~~~
/usr/include/c++/12.2.0/bits/ranges_util.h:445:7: замечание: вывод/подстановка аргумента шаблона неудачна:
/home/***/Projects/cpp/testing/source/main.cpp:289:22: замечание: кандидат ожидает 4 аргумента, 2 предоставлено
289 | std::ranges::find(lpTest, Test{5, 7});
| ~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~
/usr/include/c++/12.2.0/bits/ranges_util.h:459:7: замечание: candidate: «template requires (input_range) && (indirect_binary_predicate) constexpr std::ranges::borrowed_iterator_t std::ranges::__find_fn::operator()(_Range&&, const _Tp&, _Proj) const»
459 | operator()(_Range&& __r, const _Tp& __value, _Proj __proj = {}) const
| ^~~~~~~~
/usr/include/c++/12.2.0/bits/ranges_util.h:459:7: замечание: вывод/подстановка аргумента шаблона неудачна:
/usr/include/c++/12.2.0/bits/ranges_util.h:459:7: замечание: constraints not satisfied
In file included from /usr/include/c++/12.2.0/compare:39,
from /usr/include/c++/12.2.0/bits/stl_pair.h:65,
from /usr/include/c++/12.2.0/bits/stl_algobase.h:64,
from /usr/include/c++/12.2.0/bits/specfun.h:45,
from /usr/include/c++/12.2.0/cmath:1935,
from /usr/include/fmt/format.h:36,
from /home/***/Projects/cpp/testing/source/main.cpp:1:
/usr/include/c++/12.2.0/concepts: В подстановке «template requires (input_range) && (indirect_binary_predicate) constexpr std::ranges::borrowed_iterator_t std::ranges::__find_fn::operator()(_Range&&, const _Tp&, _Proj) const [с _Range = main()::Test (&)[50]; _Tp = main()::Test; _Proj = std::identity]»:
/home/***/Projects/cpp/testing/source/main.cpp:289:22: required from here
/usr/include/c++/12.2.0/concepts:336:13: required for the satisfaction of «invocable» [с _Fn = std::ranges::equal_to&; _Args = {main::Test&, main::Test&}]
/usr/include/c++/12.2.0/concepts:340:13: required for the satisfaction of «regular_invocable» [с _Fn = std::ranges::equal_to&; _Args = {main::Test&, main::Test&}]
/usr/include/c++/12.2.0/concepts:344:13: required for the satisfaction of «predicate» [с _Fn = std::ranges::equal_to; _I2 = const main::Test*; _I1 = std::projected]
/usr/include/c++/12.2.0/bits/iterator_concepts.h:716:13: required for the satisfaction of «indirect_binary_predicate» [с _Range = main::Test (&)[50]; _Proj = std::identity; _Tp = main::Test]
/usr/include/c++/12.2.0/concepts:336:25: замечание: the expression «is_invocable_v [с _Fn = std::ranges::equal_to&; _Args = {main::Test&, main::Test&}]» evaluated to «false»
336 | concept invocable = is_invocable_v;
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
* The terminal process "/usr/bin/bash '-c', '/usr/bin/g++ -fdiagnostics-color=always -O3 -mavx /home/raspredval/Projects/cpp/testing/source/*.cpp -o /home/***/Projects/cpp/testing/bin/release/out -Wall -Wextra -Wconversion -Wpedantic -Werror -std=c++20 -lfmt'" terminated with exit code: 1.
@@elia0162 Probably not. That’s the problem.
@@TheArtikae lol wtf it is messed up
Or read any compile error that has anything to do with the wrong data type.
Testing LANGUAGES speed by calling functions handled by OPERSTING SYSTEM is like comparing milk quality by comparing their price - may look connected, but sometimes can fool you
This video is anti c++ propaganda watch out for these litteral python snakes
yeah that's right bro😂😂
Знищимо Гадину!
I mean ya, but in an extremely io-throttled environment you’re basically testing every component *except* the language itself
As someone who is a c++ programmer who also does a bit of python occasionally, sure, as others have pointed out, there's ways of making the c++ version much faster. But unless I really needed the optimization, for something simple like this, I'd probably use python.
well yeah thats why python was invented i guess
How do you start as a programmer and what should be learnt to pass as a programmer myself? I only know std::cout, struggling with std::cin, and thought namespace is useless.
0:56 The maths ain't mathing here 🗿
C++ is super easy, just need another 2 more lifetimes to master it
lol, it IS easy, in fact, it is way easier than c for example
@@Raspredval1337 you think so? Do you mind explaining why is that the case (I think C++ is way harder, the amount of syntax and features are just insane)?
@@Raspredval1337 wtF?
@@Raspredval1337 yeah especially when you should be doing c in another few more lifetimes, but that lifetime lifespan you're having is 50+ years < my lifetime lifespan of 2 lifetimes Xd
@@Raspredval1337 C++ is like Soldier from TF2: very easy to learn, extremely hard and long to master.
Horrors: Not scary
This video: 💀
C++ is slower than python. It's like a joke because python itself written in C++ and you are saying C++ is slower 😂😂😂
that jump scare at the end scared the hell out of me
Now imagine if we try python for games 💀
import pygame
@@davidwuhrer6704 One can use Pycharm and pygame. But it'll be much harder since most game engines use C#. So, you've to do it without Advanced features which increase the difficulty level tremendously.
@@Sumirevins Akshually scripting in python does not sacrifice any features, quite the opposite, it makes them more accessible and adds new ones.
Nor is scripting in python more difficult that writing C#. One of the major selling points of python is how easy it is to write something readable in it.
And most game engines are written in C++. Only Microsofties use C#.
The reason here is that Python doesn't read and write the line into a string, it's only reading the new line characters from the stack and counting. C++ is reading and writing every line into the heap, this is vastly different and therefore the reason it runs slower.
Then what's the optimized code? Can you show me?
@@andrewwhiteman8892
```cpp
int count = 0;
for (char c = cin.get(); cin; c = cin.get()) {
if (c == '
') {
count++;
}
}```
Chars live in the stack.
@@aaarkid remember to unsync with cstdio and you're gold pony boy
@@aaarkidI just tried this code and the perfomance is worse than the one in the video, the best method I found was to read the file with fstream, it became insanely faster, and when we read the whole file with Python its performance keeps the same
Now disable sync: std::ios_base::sync_with_stdio(false);
Or better yet, use this for reading:
FILE *fin, *fout;
int rpos; char rbuf[BUFSIZE];
int wpos; char wbuf[BUFSIZE];
static inline void initRead() {
rpos = BUFSIZE - 1;
}
static inline char readChar() {
if ( !(rpos = (rpos + 1) & (BUFSIZE - 1)) )
fread( rbuf, 1, BUFSIZE, fin );
return rbuf[rpos];
}
This code only does what it is supposed to if buffsize is a power of 2. Also why are you defining a write buffer???
Still really cool code thanks for sharing :)
@@kaloka521 I copied the code from another project which also had to write to the file and forgot to remove that, oops
Why when people want to show a fast C++ they always comes to pure C? 😂
i have done alot of coding in both cpp and python, and honestly, cpp feels alot more comfortable. one of my friends said this : "when i code in cpp, it feels like i m coding, but in python, it feels like writing english."
My sht has more wisdom than your friend.
Literate programming at last. Don Knuth will be so happy.
And then every Python dev ever looks at that statement and says something like "I know. Isn't it great?!?"
You need to call std::ios_base::sync_with_stdio(false); before doing this if you want fast performance. Example is made by an unexperienced dev.
"Python" written completly wrong in the end ;) Love it....
-O3 enables some aggressive optimisations and TRIES to vectorize it, but, since the user didn't specify the vectorization options available to the compiler, it didn't vectorize it. Just pass -msse or -mavx to the compiler and you'd see the difference. Plus std::iostreams are kinda slow, should've used the cstdio primitives.
It might be purely because iostrams are slow.
I looked at the disassembly of some C code i wrote that is of the same function but uses read() directly, it did actually vectorize something - it doubled the instruction count and there is vector register manipulation everywhere, but this had almost no effect on performance compared to an unoptimized version; however both were as fast as python, as a speed about twice that of the optimized C++ version.
i would assume the same happens to the C++ code if you remove iostreams, although i did not examine that for some reason.
C++ streams are slow because they are forced to wait to sync with C's stdio by default. There's a parameter in std::ios_base that you can change to disable sync with C stdio which makes C++'s streams much faster. Obviously they are still slower than raw stdio because streams internally make a bunch of checks to convert the data that you're inputting/outputting to and from the streams.
@@AlFredo-sx2yy just paste
std::cin.tie(0); std::cout.tie(0); std::io_base::sync_with_stdio(false);
before doing any IO and cin and cout should be same speed as scanf and printf (iirc cin and cout are even faster than scanf and prinf with this)
@@___Gustav yep, those are the settings i talked about in my comment
Thank you for validating my python dreams
It's because there is a mutex to have thread safety with cin and cout in c++. You can disable it. And Python is monothreaded so there is no mutex needed.
By the time python reads the input buffered in memory, C++ has done 700 000 stdin read calls of arbitrary length. It's like reaching for a shelf in the same room and walking a few blocks to get a book.
This video is exactly the reason why I will always get paid more than pythonists.
The only thing I was scared was the word "phtyon"
it's probably because sys module is implemented with cpython, so you're essentially comparing c against c++ otherwise looping in python is extremely slow
It's not that, actually. The looping is still happening in python. Tore Braathen's explanation (I/O is the bottleneck here) is the more accurate one.
C++ IO is slow by default because C++ streams are programmed to sync with C's IO. There's a parameter in std::ios_base that you can use to disable that sync and that would make any IO operation in C++ much faster.
@@dani3645 oh i see thanks for sharing
@@AlFredo-sx2yy ♥️also getline returns std::string here and then is discarded
Ur channels gonna blow up. I was never wrong and never will be.
That doesn't mean C++ is slower. That means you suck at algorithms 😏
Also at spelling -- 1:10
And you suck at jokes lol
I've done this by accident when working on college project, my nerd friend lost his shit when he saw my absolute disaster of a code I've created. He literally screamed "NO WHAT ARE YOU DOING?!?"
That scared the shit out of me.
This is like comparing a farmer truck to the Ferrari and see which one will carry more weight
Look up the C++ function "sync_with_stdio" - this video is a classic beginner mistake by forgetting to call this function :p
That should be called how to get c++ developer angry and deal emotional damage :D
you arent scaring me, you're just making me concerned with that inefficient c++ code
Truth. I suspect that the c++ was just slower because of the branching from the if statement
@@thelemoid not even that, the fact alone that a std::string is being used is enough for me to be annoyed at this. std::string classes are mutable, while the strings in python are immutable (reminder that python is backed by c). trying to argue that python is faster than c++ while not even using the same data types.
after rewriting the C++ code to read into a char buffer, i get pretty much the exact same time as python (which is exactly to be expected since python is also just doing c stuff under the hood)
if i rewrite to use buffered input, i could definitely improve the speed by a lot more but im lazy right now lmao
Fun video. Nothing against some lang-rage-bait every now and again.
Would have been interesting if you had a second part (or separate video) where you dug deeper and understood the reason the result was what it was. Look deeper into Pythons file implementation for example (since I take it you probably prefer digging there rather than in C++'s std).
The file was a paid actor
how to scare a c++ programmer? take their thigh high socks away
Haha nice one. Well on a serious note this is just simple print operation and a counter. When writing more complex things Python provides libraries which are generally slower than C++. If you implement the same thing in Python yourself you can get equal speed etc. But Python is preferred because of its easy syntax and support of a LOT of libraries which allow you to do anything rather than implementing them. (C++ have as well, but Python has more)
Such a good edit! That typo at the end tho 👀 lmao
Tell me you skipped your data structure classes during pandemic without telling me that you skipped your classes. 😄
This an I/O efficiency issue. Nothing to do with data structures
@@benloud8740Not if you knew iostream is slow and there's another way for this
Very good thumbnail
Try it with std::ios_base::sync_with_stdio(false) at the beginning of the main function
When an endeavour os user sees his fellow endeavouros user 👀
Python isn't that much different from C++ in some ways. I have learned some Swift, C,C++, Rust, Python, Nim and probably more from the C/C++ family of language as well as several more from other families of languages. All the languages from the "C/Algol family" are much the same. They are all imperative languages with a similar syntax. Languages like Haskell and Prolog are totally different, they don't feel like your programming in the same way and you need to convert the programs from an imperative train of thought to a declarative logic. The biggest difference between Python and C++ is that Python is interpreted and doesn't have the duality of compile time vs runtime. I cannot comprehend how people can use dynamic languages for big projects, I get nervous just thinking about it. Python is great for engineers and data scientist and using jupyter notebook is an incredible tool where you can do things in a way that maybe wasn't feasible before. But actually creating application software in it sounds almost irresponsible unless your writing millions of unit tests(and some do).
depends on the project... python developers are cheaper, also it IS quicker to build something in python... then, it is also possible to design things wrong - and for c++ that could be costlier... no programming language prevents errors from happening, in C++ they can be harder to diagnose and fix than in python
DIVIDED BY PYTHON AND C++ , UNITED BY C.
clearly the problem is you used namespace std
This scared me as a Python Dev...
my benchmarks:
py3: ~0.490
c++: ~0.800
I/O operations are very long, that does not depend on the language, and the times should thus be about the same.
However python has I/O code more optimized than this C program written in 5 seconds, using less I/O operations thus the faster time.
Optimizinf the C++ code by ditching C++ because i can’t write it, and rewriting it in C reading chunks of 2048, i can get it down to 0.465, which beats python ever so slightly, probably due to load times or something.
That's the shitty part about C++. Reading file line by line is very common idea. To do it efficiently you need to do lots of steps.
In fact in C++ I avoid them entirely and read whole file. And only ~5 years ago c++ got normal api for telling file sizes.
No, rewiding file to the end, using tellg, rewinding to beginning is not normal.
I think it would be faster to allocate 1 chunk of memory for the file
@@ItsCOMMANDer_ That could be faster, but memory allocations are quite fast on modern systems, and by doing that you lose the ability to re-use the code for reading from files on unknown length. It, as almost always, depends on context
@@chri-k you can do something like a function, wich takes an FILE object, uses fseek to go to the end of the file, say at what character it is (e.G. 25 charcater is theast so the contwnt of the file is 25 bytes.
(not including \0 ) long and then just allocatge memory for that amount and use fread to read the entire file.
That's the exact reason why any simple app now is bigger and slower that an entire OS back in 1995.
Even scarier: show them C-style data oriented code that's faster than their fancy 500 level hierarchy of classes and templates to get the job done
Delusional. Practically all abstraction except polymorphism are resolved at compile time.
C has a very clean and understandable look but C++ is more powerful, it's just the truth.
Try benching any code.
Except that templates are only a compile-time cost? The actual generated code can be the same? You're not as clever as you think
@@torshepherd9334 But think of how easy the code would be to read and debug without those stupid templates!
@@torshepherd9334 templates are such a nice convenience when it comes to writing code, but a major pain in the rear when it comes to reading it as an outsider. I'd rather not touch those things beyond aliasing composite types, and maybe one or two inliners.
500 level class hierarchy is more a Java thing, not really a C++ thing.
With 4years coding C++, I can confirm that this is terrified
It is pointless to compare lang speeds with io operations cause it is system operations and from language you just call same system functions
cope.
@@Pineapple0 nah, facts
@@Pineapple0 printf is notoriously slow and many devs have warned against it.
Better to compare micropython to C using the print function via UART
the title said this would scare C++ programmers, but it looks like it just made them all angry
I just learn phtyon and I not understand why ptrin() function doesn't working?
ptrin?
it's print
@@israelsanchezcabrera4735 XD
I like how this vid is a joke but it still got C and C++ coders up at arms.
More power to you guys, I kneel! Lmao
The thing that scares me about python is not so much the performance (not everything needs to be lightning fast), but rather the lack of curly braces and static typing which can easily get messy and confusing if you're not careful
I disagree. Most interesting projects benefit from speed/efficiency gains.
@@sifagayev7793 I think you didn't understand the comment or replied to the wrong one
@@tuluppampam yeah, odd. It's not even an edited comment. oh well.
I will never be able to sleep again remembering your poor written C++ code
The problem are IO operations which are not meant to be used on production by any means. In any real C++ application (Most probably a multimedia system) console outs and console ins are a big no no.
In audio programming for example, there is a constant loop through really small slices which together makes frequencies and therefore sound. In the loop you should never use a cout or cin for debugging because it will damage completely the audio output.
When python programmers get to know that they run C under the hood
When python programmers realize they don't need to deal with C shite under the hood
I love both languages. Python bc it's easy to make a project, and C++ bc I feel like a pro programmer when programming in it.
But Im seeing that the purpose of this video actually worked, there are so many C++ devs scared in comments. Including me
Me: gets 3 errors and 5 bugs in C++
Also me: *draws the gemini card*
To solve this riddle:
Ptyhon has many library functions that are natively coded in C and quite optimized (using low level system calls and stuff)
As long as you use those packages, you will probably beat most languages (because C is very fast, if optimized)
paradox : the python interpreter is written in C.
Потому что ввод надо считывать с помошью буфера. В питоне это уже всё оптимизировано
Why did the Python developer cross the road? To avoid a "Segmentation Fault" in C++ land-they prefer their crashes to be more graceful!
Nah just ask them try to print "b" + "r"*8
*Cries in unity game dev*
python so slow
Python programmers : Thanks 🥲🥲
C programmers :
Outside : Scary?! Us?! 😂
Yt comment : Write whole c history to prove they are not scary
Java programmers : You guys even write code to write 1 million lines. It is more easy for us to write those 1 million lines.
For me, the weird thing is that it's a bit complicated and hard for me to know python but for some reason I understand c++.. I don't know why but that just happened
Although I actually managed to make turtle python art only circles and lines but in C++ basically just made my custom header file so instead using cout, I use print.. (I like to see the world burn slowly and painfully)
same bro
Thumbs up! I'm a C++ programmer and I'm scared. Delivered as promised.
Ok, that's fun, but I also wonder why that could be the case. Maybe because Python uses optimized C code to accelerate IO operations?
It all depends on how you write your code that determines the speed
This was s compiler directive issue actually...
@@cpK054L I'm talking about most cases not specifically this one, but yeah
Python is just a working interpreter for pseudocode and it's just the beginning of its advantages.
Time complexity concept left the chat
C++ programer: “Aapne toh hmse hmara guroor hi chin liya”
The cat is the programmer, always was
It is the other way round: most programmers are cats!
I'm crying and shaking rn, it's supposed to be harder because it's better I can't believe this reeee
Conspiracy... I don't wanna come back to this vid, ever again... Why do you mean if I like it, i just might
C# and Java Programmers be like -
He he set more classes and make one numeral shall we ?
Animation ,hraphics entered the chat
I did a C++ program that simulate the result of throwing a dice 10 million times. Then, I did the same algorithm in Python.
C++ did it in like 0,5 secs, while Python lasted a few seconds.
Ask c++ dev to link a library they didn't write.