Easy noob question (probobly) :)

This is a discussion on Easy noob question (probobly) :) within the C++ Programming forums, part of the General Programming Boards category; Is there anything wrong with this code, I keep getting error messages when I try to compile it: Code: #include ...

  1. #1
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    Thumbs down Easy noob question (probobly) :)

    Is there anything wrong with this code, I keep getting error messages when I try to compile it:

    Code:
    #include <iostream>	
    
    using namespace std;
    
    int main;
    
    {
        int n
        
        cout<<"5+1= ";
        cin>> n;
        cin.ignore();
        if ( n = 6 ) {
             cout<<"Good Job! That was fun right?"
             }
        
        cin.get();
    }
    Update: i get an error on line 7, It says

    invalad function direction

    Hmmmmmm
    Last edited by aaronson2012; 04-10-2008 at 05:14 PM.

  2. #2
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    There are several problems in your code, but they are all easy to fix.

    First,
    "int n" should be follow by a ";"

    second,
    = means to assign something, while == is to compare.
    Try changing if(n = 6) to if(n==6)

    third,
    int main() should return something, Try adding return 0 at the end of main. Also, main is a function, and should not have ; at the end

    Code:
    #include <iostream>	
    
    using namespace std;
    
    int main
    {
        int n;
        
        cout<<"5+1= ";
        cin>> n;
        cin.ignore();
        if ( n == 6 ) {
             cout<<"Good Job! That was fun right?";
             }
        
        cin.get();
    return 0;
    }
    Last edited by h3ro; 04-10-2008 at 05:09 PM.

  3. #3
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    >> also, int main should return something. Try adding return 0 at the end of main
    That's not actually necessary, there's a special rule with main that says it's ok not to. The code is fine (except for the == thing).

  4. #4
    Captain Crash brewbuck's Avatar
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    Three problems, highlighted in bold and red:

    Code:
    #include <iostream>	
    
    using namespace std;
    
    int main;
    
    {
        int n;
        
        cout<<"5+1= ";
        cin>> n;
        cin.ignore();
        if ( n == 6 ) {
             cout<<"Good Job! That was fun right?";
             }
        
        cin.get();
    }

  5. #5
    C++まいる!Cをこわせ! Elysia's Avatar
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    Quote Originally Posted by h3ro View Post
    There are several problems in your code, but they are all easy to fix.

    First,
    "int n" should be follow by a ";"

    second,
    = means to assign something, while == is to compare.
    Try changing if(n = 6) to if(n==6)

    third,
    int main() should return something, Try adding return 0 at the end of main. Also, main is a function, and should not have ; at the end

    Code:
    #include <iostream>	
    
    using namespace std;
    
    int main()
    {
        int n;
        
        cout<<"5+1= ";
        cin>> n;
        cin.ignore();
        if ( n == 6 ) {
             cout<<"Good Job! That was fun right?";
             }
        
        cin.get();
    return 0;
    }
    That doesn't compile either because you forgot the part in red.
    Quote Originally Posted by Adak View Post
    io.h certainly IS included in some modern compilers. It is no longer part of the standard for C, but it is nevertheless, included in the very latest Pelles C versions.
    Quote Originally Posted by Salem View Post
    You mean it's included as a crutch to help ancient programmers limp along without them having to relearn too much.

    Outside of your DOS world, your header file is meaningless.
    For information on how to enable C++11 on your compiler, look here.
    よく聞くがいい!私は天才だからね! ^_^

  6. #6
    Its hard... But im here swgh's Avatar
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    I personally feel that the standard should ensure main returns a value.

    You explicity say int main(), so in essence, you are telling the function that it will return an integer value when the function terminates. If main is ok to not return a value, then why do some compilers throw an error when you use void main()? seems like it is a bit like double standards.
    I'm just trying to be a better person - My Name Is Earl

  7. #7
    Cat without Hat CornedBee's Avatar
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    main() must return a value - it's just that the compiler is required to implicitly add a return 0 if you don't.
    All the buzzt!
    CornedBee

    "There is not now, nor has there ever been, nor will there ever be, any programming language in which it is the least bit difficult to write bad code."
    - Flon's Law

  8. #8
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    I personally feel main should be void, just like how it is in Java, for the sake of portability. But, of course, there is C compatibility to worry about, too.

  9. #9
    Cat without Hat CornedBee's Avatar
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    C compatibility would be easily handled by allowing main to be int, but making the canonical form void.

    A more interesting question is the effect that calling exit() would have on local objects with destructors.
    All the buzzt!
    CornedBee

    "There is not now, nor has there ever been, nor will there ever be, any programming language in which it is the least bit difficult to write bad code."
    - Flon's Law

  10. #10
    C++まいる!Cをこわせ! Elysia's Avatar
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    Quote Originally Posted by cyberfish View Post
    I personally feel main should be void, just like how it is in Java, for the sake of portability. But, of course, there is C compatibility to worry about, too.
    I feel that would be stupid seeing as how it would break 99% of the programs out there written for platforms with CLI in mind or otherwise, especially since they can return a value telling of success or failure or whatever.
    I feel Java is wrong. A return code can tell a thousand words.
    Quote Originally Posted by Adak View Post
    io.h certainly IS included in some modern compilers. It is no longer part of the standard for C, but it is nevertheless, included in the very latest Pelles C versions.
    Quote Originally Posted by Salem View Post
    You mean it's included as a crutch to help ancient programmers limp along without them having to relearn too much.

    Outside of your DOS world, your header file is meaningless.
    For information on how to enable C++11 on your compiler, look here.
    よく聞くがいい!私は天才だからね! ^_^

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