This is straight up gaslighting

:/ the second paragraph is still wrong. Output iterators have nothing to do with streams and operator<< (other than std::ostream_iterator being an output iterator, but that still is about assignment, not <<) Forward iterators are still not output iterators by default, as seen from the godbolt example. the const iterator was a forward iterator, but since assignment was invalid to the dereferenced vector, it was not an output iterator. the normal iterator was both a forward and an output iterator. I intentionally chose std::vector<std::vector<int>> because then operator<< won't exist for sure.

anyone know open gl?

I did not even mention tags Support ≠ guarantee. Guarantee is only available when the forward iterator is also an output iterator (forward iterator + output iterator == mutable forward iterator). This guarantee is what my initial question was and what I was talking about repeatedly. I never changed that. You didn't address the stream and << parts

how do i specify T to be both an std::output_iterator and an std::forward_iterator?

What can be more clear than this first message.

no i want T to satisfy both output iterator and forward iterator requirements

And this second message

Yes that was my mistake.

oh sorry. i forgot that const T& is also an lvalue

.

Forward iterator is not much more (i assume by "much more" you mean superset) than output iterator. It's different. Since not all forward iterators are output iterators.

That is agreeable

*x = value; should work for some forward iterator x

I did provide this and others where it was clear i wanted to assign to *x

Well

------o------ I hope everyone's popcorn is finished by now

I get that when someone says anything other than an input iterator, mutability is often assumed. I was talking about std::output_iterator specifically because i did not want to make the assumption and joining the std::output_iterator concept provided the guarantee without the need to make the assumption.

But i know how to do that with type traits already. I specifically wanted the concepts

So asked that

Guys i have a question When i am writing a code in c++ Should i right at the top of my code Using namespace std? Many people just write std::cout every time in things like that instead

Guys i have a question When i am writing a code in c++ Should i right at the top of my code Using namespace std? Many people just write std::cout every time in things like that instead

Don’t

write std:: explicitly

Duplicates may occur

Okay but i am using simple programs can u specify what does duplicates mean because i have read about this topic and i donot get what they mean with duplicate

Guys i have a question When i am writing a code in c++ Should i right at the top of my code Using namespace std? Many people just write std::cout every time in things like that instead

it's "ok" to use that in source files

but not on header files, as the namespace use propagates

a slightly better option is to use using std:: vector and so on

a slightly better option is to use using std:: vector and so on

This

a slightly better option is to use using std:: vector and so on

but yet again, not on header files

Okay i got it. Thanks

Could someone kindly tell me why string and int variables stored in 24 and 4 bits respectively? I'm fairly new to programming.

*variables are stored in

Also *bytes, not bits

Hi

Could someone kindly tell me why string and int variables stored in 24 and 4 bits respectively? I'm fairly new to programming.

std::string is not a primitive data type. It is a class, like a struct. A class can contain properties. The size of it depends on its properties. Why is int 4 bytes, because it is 32 bit integer, meaning it requires 4 bytes to store the value. Some aliases you need to know: char = int8_t is 8 bit integer, so it is 1 byte. short = int16_t is 16 bit integer, so it is 2 bytes. int = int32_t is 32 bit integer, so it is 4 bytes.

std::string is not a primitive data type. It is a class, like a struct. A class can contain properties. The size of it depends on its properties. Why is int 4 bytes, because it is 32 bit integer, meaning it requires 4 bytes to store the value. Some aliases you need to know: char = int8_t is 8 bit integer, so it is 1 byte. short = int16_t is 16 bit integer, so it is 2 bytes. int = int32_t is 32 bit integer, so it is 4 bytes.

But how is it(int) then able to store integer values larger than 4 characters, say 11111 for example.

But how is it(int) then able to store integer values larger than 4 characters, say 11111 for example.

You should think in binary.

std::string is not a primitive data type. It is a class, like a struct. A class can contain properties. The size of it depends on its properties. Why is int 4 bytes, because it is 32 bit integer, meaning it requires 4 bytes to store the value. Some aliases you need to know: char = int8_t is 8 bit integer, so it is 1 byte. short = int16_t is 16 bit integer, so it is 2 bytes. int = int32_t is 32 bit integer, so it is 4 bytes.

lil correction: char is uint8_t

lil correction: char is uint8_t

uint8_t is unsigned char actually.

Yeah binary. But won't one character be stored in one byte regardless of what it is.

lil correction: char is uint8_t

char signess is implementation defined

char signess is implementation defined

yeah, fair

But how is it(int) then able to store integer values larger than 4 characters, say 11111 for example.

Position based system

Same deal as 100 vs one hundred sticks to represent the number

Yeah binary. But won't one character be stored in one byte regardless of what it is.

1 character is indeed stored in one byte. But this: int x = 1000; Does not mean the memory stores 4 chars that contain '1', '0', '0', '0'.

How can 10000 be stored between 548825435840 and 548825435844 ? (Five bytes in 4 bytes' memory) ?

How can 10000 be stored between 548825435840 and 548825435844 ? (Five bytes in 4 bytes' memory) ?

It is not '1','0', '0', '0', '0'

It is not '1','0', '0', '0', '0'

Yeah, I understand it is not binary 1 0 0 0 0, buy either way it each of them should take 1 byte, 5 bytes in total isn't it. Take 20000 otherwise.

1 character is indeed stored in one byte. But this: int x = 1000; Does not mean the memory stores 4 chars that contain '1', '0', '0', '0'.

10000 sir, not 1000

Yeah, I understand it is not binary 1 0 0 0 0, buy either way it each of them should take 1 byte, 5 bytes in total isn't it. Take 20000 otherwise.

UINT_MAX is 4294967295

How can 10000 be stored between 548825435840 and 548825435844 ? (Five bytes in 4 bytes' memory) ?

int x =10000; in binary representation is 00000000000000000010011100010000 It takes 32 bits (count the binary digits, leading zero may not be written, but it is still stored in memory). That means in your physical memory (RAM) stores 00000000000000000010011100010000 at some location. 32 bits is 4 bytes. That is why integer 4 bytes.

Yeah, I understand it is not binary 1 0 0 0 0, buy either way it each of them should take 1 byte, 5 bytes in total isn't it. Take 20000 otherwise.

It is exactly binary lol

And oddly enough integer which is 32 bits can store 2^32 different states

@Ishikawa I think you should learn computer organization and architecture first. It is the fundamental of your above question.

int x =10000; in binary representation is 00000000000000000010011100010000 It takes 32 bits (count the binary digits, leading zero may not be written, but it is still stored in memory). That means in your physical memory (RAM) stores 00000000000000000010011100010000 at some location. 32 bits is 4 bytes. That is why integer 4 bytes.

40 bits sir, not 32. Hence 5 bits.

No no no, it assumes "10000" as chars, not integer.

40 bits sir, not 32. Hence 5 bits.

Please explain a lil bit more

Even more so it fits in just two bytes

Please explain a lil bit more

Think about 2 based positioned number system.

Where each bit is 2 to the power of the bit's order

Your converter works like this: Convert '1' to ASCII number, convert the number to binary. Convert '0' to ASCII number, convert the number to binary. Convert '0' to ASCII number, convert the number to binary. Convert '0' to ASCII number, convert the number to binary. Convert '0' to ASCII number, convert the number to binary. Char is 8 bit, that is why you get 40 bits.

Where each bit is 2 to the power of the bit's order

Oh! Now I get it.

Your converter works like this: Convert '1' to ASCII number, convert the number to binary. Convert '0' to ASCII number, convert the number to binary. Convert '0' to ASCII number, convert the number to binary. Convert '0' to ASCII number, convert the number to binary. Convert '0' to ASCII number, convert the number to binary. Char is 8 bit, that is why you get 40 bits.

Got it. Thank you very much.

0b1101 = 1 * 2^3 + 1 * 2^2 + 0 * 2^1 + 1 * 2^0 = 8 + 4 + 0 + 1 = 13

0b1101 = 1 * 2^3 + 1 * 2^2 + 0 * 2^1 + 1 * 2^0 = 8 + 4 + 0 + 1 = 13

*fixed

Search for "Number Base Conversion" on YouTube and watch it.

I know that conversion. I just could not thik that way and converted each byte separately. Thank you very much kind people.

But again, how do string variables store more than 24 characters?

But again, how do string variables store more than 24 characters?

std::string is a class, it has dynamic allocator that allows you to store chars dynamically. For example: std::string x; x = "Hello World"; Internally, x holds a pointer to the heap (this is where the "Hello World" stored). When there is a read/write operation to the string value, it uses the pointer to read/write the value.

It actually has a complex way to do that internally. That is just a simple illustration.

std::string x; x = "Hello World"; In this case, sizeof(x) is only the size of the class. Not the length of the string stored.

Got it. Thanks again. 😁😁

typedef basic_string<char> string; So string is an alias for basic_string<char>.

This is how basic_string class implemented https://github.com/gcc-mirror/gcc/blob/master/libstdc%2B%2B-v3/include/bits/basic_string.h

Anyone solve this please

Anyone solve this please

Does that even compile?

No it will not compile but tell me the logic

No it will not compile but tell me the logic

Logic of what?

@ammarfaizi2 Ah, I see, you are a man of culture as well.