static array as a class member

[stmfc]

what is wrong with the code below,
when i compile i get the following error:

ld:
Unresolved:
myClass::myArray

but when i dont use the keyword static while declaring the array,
there is no problem. what is the story about static arrays in class

***********************

#include <iostream>
using namespace std;
 
class myClass{
private:
        int a;
        static int myArray[10];
public:
        myClass();
        void display();
};
 
int main()
{
        myClass A;
        A.display();
 
        return 0;
}
 
 
myClass::myClass()
{
                for(int i=0; i<10; i++)
                        myArray[i]=i;
}
 
void myClass::display()
{
        for(int i=0; i<10; i++)
                cout<<myArray[i]<<" ";
        cout<<endl;
}
 
*****************************

[svlsr2000]

what is wrong with the code below,
when i compile i get the following error:

ld:
Unresolved:
myClass::myArray

but when i dont use the keyword static while declaring the array,
there is no problem. what is the story about static arrays in class

***********************

#include <iostream>
using namespace std;

class myClass{
private:
int a;
static int myArray[10];
public:
myClass();
void display();
};

int main()
{
myClass A;
A.display();

return 0;
}


myClass::myClass()
{
for(int i=0; i<10; i++)
myArray[i]=i;
}

void myClass::display()
{
for(int i=0; i<10; i++)
cout<<myArray[i]<<" ";
cout<<endl;
}

*****************************

Storage for static members is not allocated by compiler, its only allocated by linker.
Please correct me if i am wrong.
You need to initialize static member variables globally, to have space allocated for it.

class A{
public:
static int i;
};
//Needs to initialize i
int A::i=0;

[stmfc]

but when i declare int a, as static int a
in the class declaration, there is not any problem

[Prasannaa]

Hi ,

The reason , why you don't get error
when you declare "int a;" as "static int a;" is because you are not using it
anywhere in the code, if u use it then you will get the link error.

Regards
Prasannaa.