My first program and it doesn't work.

PHP Code:

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    #include <iostream>
    int main()
    {
        std::cout << "Enter two numbers:" << std::endl;
        int v1, v2;
        std::cin >> v1 >> v2;
        std::cout << "The sum of " << v1 << " and " << v2
                  << " is " << v1 + v2 << std::endl;
        return 0;
    } 


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Could anyone tell me what's wrong with that? I've bought a book on C++ and all I get are compiler errors, such as;

"'cout' is not a member of 'std'"
"'endl' is not a member of 'std'"
"'cin' is not a member of 'std'"
"'cout' is not a member of 'std'"

Obviously this is related to the 'std'. I've seen online tutorials not use the 'std' at all. Basically what I want to know is how I could fix that program, what 'std' is all about and finally why 'std' is used in some tutorials and not others.

Any help will be much appreciated. :)

what compiler?

Try this

Code:

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#include <iostream>
using namespace std;

int main()
{
  cout << "This should display." << endl; //no need for std::

return 0;
}

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Wow, that was fast. :D

I'm using Bloodshed Dev-C++, is that a problem? I've tried your version of the program and it gave me a whole new set of errors.

See for yourself, screenshot: http://img149.imageshack.us/img149/8...eenshot1cy.jpg

According to Bjarne Stroustrup, you should try this program to see if the compiler's conforming to the ISO standard. Dev-C++ does, so I have no idea why this doesn't work. Have you tried uninstalling it then reinstalling it - worth a try?

http://www.research.att.com/~bs/compilers.html

Ooo update: Are you using the Dev-C++ 5 beta? My friend who's also learning to program has informed me that it didn't work; he had similar problems. Get the next v down [v4.9.9.3 if I remember].

hmm... let's see, did you install the full package, or only the IDE?
If you dont have a compiler set, you cant compile your programs.

The version of Dev-C++ that you are using comes with an updated compiler (so the example should work), but if you choose to download and install the Dev-C++ IDE only, then there's no compiler to compile with.

Well I only installed Dev-C++ today and I'm running 4.9.9.2 (It's been on my desktop a while). I could try reinstalling, but as I said I've only installed it today...

Do you think I should try a different compiler?

Quote:

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hmm... let's see, did you install the full package, or only the IDE?
If you dont have a compiler set, you cant compile your programs.

The version of Dev-C++ that you are using comes with an updated compiler (so the example should work), but if you choose to download and install the Dev-C++ IDE only, then there's no compiler to compile with.

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Full package.

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Well I only installed Dev-C++ today and I'm running 4.9.9.2 (It's been on my desktop a while). I could try reinstalling, but as I said I've only installed it today...

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On the Dev-C++ download page, did you download "Dev-C++ 5.0 beta 9.2 (4.9.9.2) (9.0 MB) with Mingw/GCC 3.4.2" (devcpp-4.9.9.2_setup.exe) or "Dev-C++ 5.0 beta 9.2 (4.9.9.2), executable only (2.4 MB)" (devcpp-4.9.9.2_nomingw_setup.exe).

If you downloaded the latter, you should download the former and do a re-install according to the uninstall/delete/reinstall procedure.

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Full package.

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Okay, now go to the "Compile Log" tab and post your full compile log.

I'm quite sure I downloaded ("Dev-C++ 5.0 beta 9.2 (4.9.9.2) (9.0 MB) with Mingw/GCC 3.4.2"). I'm going to unistall this version (whatever it is, I'm not sure) and install (devcpp-4.9.9.2_setup.exe). Just to eliminate that.

This is what I get when I to compile this program:

Code:

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#include <iostream>
    int main()
    {
        std::cout << "Enter two numbers:" << std::endl;
        int v1, v2;
        std::cin >> v1 >> v2;
        std::cout << "The sum of " << v1 << " and " << v2
                  << " is " << v1 + v2 << std::endl;
        return 0;
    }

---

Quote:

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Compiler: Default compiler
Executing g++.exe...
g++.exe "C:\prog\ghfgjh.cpp" -o "C:\prog\ghfgjh.exe" -I"C:\Dev-Cpp\lib\gcc\mingw32\3.4.2\include" -I"C:\Dev-Cpp\include\c++\3.4.2\backward" -I"C:\Dev-Cpp\include\c++\3.4.2\mingw32" -I"C:\Dev-Cpp\include\c++\3.4.2" -I"C:\Dev-Cpp\include" -L"C:\Dev-Cpp\lib"
C:\prog\ghfgjh.cpp:1:20: iostream: No such file or directory
C:\prog\ghfgjh.cpp: In function `int main()':
C:\prog\ghfgjh.cpp:4: error: `cout' is not a member of `std'
C:\prog\ghfgjh.cpp:4: error: `endl' is not a member of `std'
C:\prog\ghfgjh.cpp:6: error: `cin' is not a member of `std'
C:\prog\ghfgjh.cpp:7: error: `cout' is not a member of `std'
C:\prog\ghfgjh.cpp:8: error: `endl' is not a member of `std'

Execution terminated

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If I try to compile this program:

Code:

---

#include <iostream>
using namespace std;

int main()
{
  cout << "This should display." << endl; //no need for std::

return 0;
}

---

I get:

Quote:

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Compiler: Default compiler
Executing g++.exe...
g++.exe "C:\prog\ghfgjh.cpp" -o "C:\prog\ghfgjh.exe" -I"C:\Dev-Cpp\lib\gcc\mingw32\3.4.2\include" -I"C:\Dev-Cpp\include\c++\3.4.2\backward" -I"C:\Dev-Cpp\include\c++\3.4.2\mingw32" -I"C:\Dev-Cpp\include\c++\3.4.2" -I"C:\Dev-Cpp\include" -L"C:\Dev-Cpp\lib"
C:\prog\ghfgjh.cpp:1:20: iostream: No such file or directory
C:\prog\ghfgjh.cpp: In function `int main()':
C:\prog\ghfgjh.cpp:6: error: `cout' undeclared (first use this function)
C:\prog\ghfgjh.cpp:6: error: (Each undeclared identifier is reported only once for each function it appears in.)
C:\prog\ghfgjh.cpp:6: error: `endl' undeclared (first use this function)

Execution terminated

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It must have been something to do with my compiler. I've reinstalled Dev-C++ using that guide you gave me. The version I have installed now is, Dev-C++ 5.0 beta 9.2 (4.9.9.2) (9.0 MB) with Mingw/GCC 3.4.2.

Both programs worked. Thanks a lot everyone! :D

I'm curious though, what is 'std::'? What's It's purpose? Why is it used if it's not needed?

It's a namespace. Think of it as a wrapper around some classes & functions to ensure no conflicts occur. This menas you could write a function named cout, and place it in a different namespace (or leave it in the global namespace) without fear of it being mis-interpreted by your compiler. I strongly reccommend you don't do that.

Quote:

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Originally Posted by Magneto

It must have been something to do with my compiler. I've reinstalled Dev-C++ using that guide you gave me. The version I have installed now is, Dev-C++ 5.0 beta 9.2 (4.9.9.2) (9.0 MB) with Mingw/GCC 3.4.2.

Both programs worked. Thanks a lot everyone! :D

I'm curious though, what is 'std::'? What's It's purpose? Why is it used if it's not needed?

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Don't worry about it.. when you get to namespaces youll see why its there ;)

Just so you know this was your error

Quote:

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C:\prog\ghfgjh.cpp:1:20: iostream: No such file or directory

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So apparantly the packages you got didnt install correctly for some reason.

Quote:

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Originally Posted by JoshR

Just so you know this was your error

So apparantly the packages you got didnt install correctly for some reason.

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Im pretty sure when i had Dev-C++ when i installed it there was something about installing the libraries. Maybe he checked that off or something.

Also one thing: make sure you install DevC++ to its default directory. People have experienced problems when they have installed it to other directories.

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Im pretty sure when i had Dev-C++ when i installed it there was something about installing the libraries. Maybe he checked that off or something.

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Yeah, there is an option and I must of not done it the first time.

Quote:

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Also one thing: make sure you install DevC++ to its default directory. People have experienced problems when they have installed it to other directories.

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Check, thanks for the advice.

Anywho, you can look forward to seeing a lot more of my problems around here (I'm sure I'll have plenty), the response time is awesome. :D