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Dec 30th, 2006

Re: Do i need C to learn C++?

also you can get free c++ videotutorials here
http://seangreasley.com/

jan1024188

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Dec 30th, 2006

Re: Do i need C to learn C++?

Click to Expand / Collapse Quote originally posted by jan1024188 ...

also you can get free c++ videotutorials here
http://seangreasley.com/

awwww sweet as! thnx man!

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Dec 30th, 2006

Re: Do i need C to learn C++?

Quote ...

omg...last question ^^

ive written and comiled the "hello world" thing using Dev-C++

when i run the exe, a dos-like window pops up for half sec and dissapears...wtf? ive read and reread over what i am meant to do...?!?!?! is that whats meant to hpn?

Add

system("PAUSE");

in front of return 0;

Last edited by Boldgamer; Dec 30th, 2006 at 12:42 pm. Reason: Sorry. I quoted the wrong person.

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Dec 30th, 2006

Re: Do i need C to learn C++?

Click to Expand / Collapse Quote originally posted by WoBinator ...

ive written and comiled the "hello world" thing using Dev-C++

when i run the exe, a dos-like window pops up for half sec and dissapears...wtf? ive read and reread over what i am meant to do...?!?!?! is that whats meant to hpn?

The program is doing exactly what it is supposed to do, the only thing being the command window closes after displaying the output.

To make the command window stay, make the program wait for some event (like accepting a key from the user) to see the expected output.

In C do getchar( ) at the end of the program.
In C++ do cin.get( ) at the end of the program.

Any other method used, is totally platform / compiler dependent and should be best avoided.

BTW even system( "pause" ) is a non-standard method which is best avoided.

~s.o.s~

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Dec 30th, 2006

Re: Do i need C to learn C++?

For a standard, safe way of getting the program to pause, you could use a function like this

CPP Syntax (Toggle Plain Text)
#include <iostream>
#include <limits>
 
void stop()
{ 
    std::cin.ignore( std::numeric_limits<std::streamsize>::max() , '\n');
    std::cin.get();
}
 
int main()
{
    stop();
}
#include <iostream>
#include <limits>

void stop()
{ 
    std::cin.ignore( std::numeric_limits<std::streamsize>::max() , '\n');
    std::cin.get();
}

int main()
{
    stop();
}

Last edited by Bench; Dec 30th, 2006 at 1:32 pm.

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Dec 30th, 2006

Re: Do i need C to learn C++?

Click to Expand / Collapse Quote originally posted by Bench ...

For a standard, safe way of getting the program to pause, you could use a function like this
CPP Syntax (Toggle Plain Text)
#include <iostream>
#include <limits>
 
void stop()
{ 
    std::cin.ignore( std::numeric_limits<std::streamsize>::max() , '\n');
    std::cin.get();
}
 
int main()
{
    stop();
}
#include <iostream> #include <limits> void stop() { std::cin.ignore( std::numeric_limits<std::streamsize>::max() , '\n'); std::cin.get(); } int main() { stop(); }

wow but this doesnt make sense

why dont you just type

C++ Syntax (Toggle Plain Text)
#include <iostrem.h>
 
using namespace std;
 
 
void main()
 {
cout << "\n" ;
cin.get();
return(0);
}
#include <iostrem.h>

using namespace std;


void main()
 {
cout << "\n" ;
cin.get();
return(0);
}

Last edited by jan1024188; Dec 30th, 2006 at 1:43 pm.

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Dec 30th, 2006

Re: Do i need C to learn C++?

@ Bench
Just to let you know that the functions cin.ignore( ) and cin.get( ) won't function as expected if the standard input stream is corrupted and its status bit not cleared. Your code is good and robust but to make it to adapt to stream corruptions, do something like:

C++ Syntax (Toggle Plain Text)
#include <iostream>
#include <limits>
 
void stop( )
{
    using namespace std ;
 
    cin.clear( ) ;
    cin.ignore( numeric_limits<streamsize>::max(), '\n' ) ;
    cin.get( ) ;
}
#include <iostream>
#include <limits>

void stop( )
{
    using namespace std ;

    cin.clear( ) ;
    cin.ignore( numeric_limits<streamsize>::max(), '\n' ) ;
    cin.get( ) ;
}

@ jan1024188
There are some cases in which the simple statement getchar( ) or cin.get( ) won't work. Those being corrupted stream, or more than a single newline character hanging in the stream.

For simple cases the primitive statements work well, but if your program is a highly CUI (console user interface) dependent, you might want to have a robust function like mentioned above by me and Mr. Bench to handle fatalitites

~s.o.s~

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Dec 30th, 2006

Re: Do i need C to learn C++?

I wouldn't put 'using namespace std' within the scope of a function.

It is better to state it at the top - just under the headers.

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Dec 30th, 2006

Re: Do i need C to learn C++?

C++ Syntax (Toggle Plain Text)
#include <iostrem.h>
 
using namespace std;
 
 
void main()
 {
cout << "\n" ;
cin.get();
return(0);
}
#include <iostrem.h>

using namespace std;


void main()
 {
cout << "\n" ;
cin.get();
return(0);
}

We've told you time and time again, don't use void main and don't use iostream.h.

But what do you do? Dearie me.

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Dec 30th, 2006

Re: Do i need C to learn C++?

Click to Expand / Collapse Quote originally posted by iamthwee ...

I wouldn't put 'using namespace std' within the scope of a function.

It is better to state it at the top - just under the headers.

Declarations are best made in the proximity where they are required to be used. Limiting the scope of the namespace declaration namespace collisions can be avoided.

Programs should be made avail of only that much functionality which concerns them hence declaring the namespace in the function was for the best.

~s.o.s~

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