Syntax of Declaring a Constructor in Header (.h) and then Defining in a Class File (.cpp) C++ [closed]

Answer 1

someclass.h file

#ifndef SOME_CLASS_H
#define SOME_CLASS_H    

class someclass
{
public:
  someclass();  // declare default constructor

private:
  int member1; 
};

#endif

someclass.cpp

someclass::someclass()   // define default constructor
: member1(0)             // initialize class member in member initializers list
{
   //implementation
}