You leave the declarations in the header file:
class A2DD
{
private:
int gx;
int gy;
public:
A2DD(int x,int y); // leave the declarations here
int getSum();
};
And put the definitions in the implementation file.
A2DD::A2DD(int x,int y) // prefix the definitions with the class name
{
gx = x;
gy = y;
}
int A2DD::getSum()
{
return gx + gy;
}
You could mix the two (leave getSum()
definition in the header for instance). This is useful since it gives the compiler a better chance at inlining for example. But it also means that changing the implementation (if left in the header) could trigger a rebuild of all the other files that include the header.
Note that for templates, you need to keep it all in the headers.