initialization of static data member

[vencent]

//class.h
class A
{  static int a;
   static int b[10];
public:
   static void set();
};

//class.cpp
#include"class.h" 
void A::set()
{
   a=0;
 for(int i=0;i<10;i++)
   b[i]=0;
}

my plan is to provide a static method to initialize static data, but it cannot compile. For variable a I find a simple way to initialize it in class.cpp file with int A::a=0. For array it is possible to int A::b[10]={0,1,2..}, but it is not appropriate for large array size. So what is wrong with my plan? it is ok to initialize all static data in class.cpp file and use it directly in main.cpp? Thanks a lot.

[PanGalactic]

Would you mind editing your post and putting the source inside code tags? It will make it a lot more legible and folks here will be more likely to look at it.

[vencent]

Thanks, I am new to C++ and this forum.
In fact, I just find it is better to set static data and methods as public, and I can assign different values to them when I use them. But still confusing why the above code doesn't work?

[guestgulkan]

static class variables need to be defined outside the class (somewhere in a cpp file)
as well as declared inside the class;

//class.h
class A
{  static int a;
   static int b[10];
public:
   static void set();
};

//class.cpp
#include"class.h" 
void A::set()
{
  //no need for this anymore
 /* a=0;
 for(int i=0;i<10;i++)
   b[i]=0;*/
}
//define the static variables.
//Note  that static Plain Old Data types like int  are zero initialised unless otherwise specified
int A:a
int A::b [10];

[vencent]

yes, but what if I want to initialize b[10] with nonzero numbers? I am thinking to use a loop, but as I declare b[] array as private. That's why I was trying to add a public static method to set b[].
The question is: how to set private static array data members? Thanks a lot.

[vencent]

guestgulkan, I just got it. I have to declare the static member data before using it, right? Now everything works as I expected, thanks a lot:)