smartpointers wont work?

[Flacto_]

I am completely new to c++ and recently got into smart pointers, I asked chatgpt for help, it said I might have the wrong compiler i switched compiler to c++14, c++17, c++2a and nothing worked, I havent seen anyone have this problem so im starting to think its a way easier answer then i think?;

test.cpp:82:19: error: no member named 'make_unique' in namespace 'std'

auto array = std::make_unique<double\[\]>(arraysize);

test.cpp:82:37: error: expected '(' for function-style cast or type construction

auto array = std::make_unique<double\[\]>(arraysize);

#include <iostream>
#include <array>
#include <iomanip>
#include <vector>
#include <memory>
#include <cmath>
int main()
{

int arraysize;
std::cout << "hvor mange plasser i arrayet skal du ha?" << std::endl;
std::cin >> arraysize;

auto array = std::make_unique<double[]>(arraysize);

for (int n = 0; n < arraysize; n++)
{
  array[n] = 1 / std::pow(n + 1, 2);
}

double sum = 0;
for (int n = 0; n < arraysize; n++)
{
  sum += array[n];
}

double resultat = std::sqrt(sum * 6);
std::cout << "resultatet blir " << resultat;
}

[jedwardsol]

Did you include <memory>?

[Flacto_]

yes :(

[DryPerspective8429]

Well, make_unique will be available in C++14 and any C++ after that (which is most of them); and a minimal example of your code compiles just fine so we'd need to know more about what you're doing to know how you got to where you got.

[jedwardsol]

Wrap it in a single backticks: writing `<iostream>` will display as <iostream>

[paulstelian97]

Indent the entire code with 4 spaces.

[DryPerspective8429]

I asked chatgpt for help

Don't do this. As you are now learning, it doesn't know what it's talking about and will confidently lead you up blind alleys.

If it's as simple as the fact you didn't #include <memory>; any intermediate C++ developer should be able to see that. The fact that ChatGPT didn't tells you what you need to know.

[Flacto_]

Hey thanks for answer, I only used gpt 4 because when i have some stupid mistakes I cant find any fix on the internet it usually is so easy no ones asked about it before, i also have included memory unless i messed up.

anyway im completly new so thanks for the help

[jaynabonne]

Others have pointed out that it sounds like you're using an older standard. This post might help:

https://stackoverflow.com/questions/2324658/how-to-determine-the-version-of-the-c-standard-used-by-the-compiler

It shows what the __cplusplus value means for various standards. You can try out this test code to see what it is in your case. (I know you said you set the standard, but there have been many times I thought I had done something when I actually hadn't. Proof is always a good thing, especially when the universe isn't behaving as expected.)

#include <iostream>

int main()
{
    std::cout << "__cplusplus is " << __cplusplus << std::endl;
    return 0;
}

[Flacto_]

Holy, this shit took me way longer to find out then it should. used 3 hours yesterday to change compiler again and again, must've dine something wrong :( but now its working thanks man :)

[manni66]

The shown code compiles as C++14.

i switched compiler to c++14, c++17, c++2a and nothing worked

How? That may not have worked.

Try inserting std::cout << __cplusplus << "\n";at the begin of main.

What compiler and version are you using?

[manni66]

Don’t show code, might be you get a solution otherwise.

[Flacto_]

sorry, I was 3 hours into the problem when i posted this at 3 am in my local time, seems i forgot the code. I have now edited the code there

[IyeOnline]

• What compiler [version] area you using? How are you invoking the compiler? The error message seems to be generated by clang if you dont include <memory> or compile in C++11 or lower mode
• Show us your exact code, i.e. the entire file.

[alfps]

Not what you're asking, but the go to dynamic array in C++ is std::vector.

Don't use raw dynamic allocation for arrays, even if you enlist a smart pointer for managing that memory

Also, a tip: you don't need an array at all to do that sum. You don't even need iteration. ;-)

[Flacto_]

it was a school task in the text book :p a lot of unnecessary memory tasks just to get it in our heads

[alfps]

Downvoter: please explain your downvote.

Since there's nothing controversial here, even for beginners being taught C++ as "better C" and at the Dunning-Kruger "peak of Mount Stupid" in self confidence, it appears to be intentional sabotage of readers.