Passing Parameters to Base Class in C++

So far, none of the preceding examples have included constructor functions that require arguments. In cases where only the derived class' constructor requires one or more parameters, you simply use the standard parameterized constructor syntax. The general form of this expanded derived-class constructor declaration is shown below:

derived-constructor(arg-list) : base1(arg-list),
base2(arg-list),
// ...
baseN(arg-list)
{
// body of derived constructor
}

Here, base1 through baseN are the names of the base classes inherited by the derived class. Notice that a colon separates the derived class' constructor declaration from the base-class specifications, and that the base-class specifications are separated from each other by commas, in the case of multiple base classes. Example:#include <iostream>
using namespace std;
class base {
protected:
int i;

public:
base(int x) { i=x; cout << "Constructing base\n"; }
~base() { cout << "Destructing base\n"; }
};
class derived: public base {
int j;

public:
derived(int x, int y): base(y)
{ j=x; cout << "Constructing derived\n"; }
~derived() { cout << "Destructing derived\n"; }
void show() { cout << i << " " << j << "\n"; }
};

int main()
{
derived ob(3, 4);
ob.show();
return 0;
}