#include <iostream>         //C++ example
#include <cstdlib>
using namespace std;

void f(int copy, int *p);   //function declaration

int main()
{
	int i = 10;
	int j = 20;

	f(i, &j);

	cout << "i == " << i << "\n"
		<< "j == " << j << "\n";

	return EXIT_SUCCESS;
}

void f(int copy, int *p)    //function definition
{
	++copy;   //has no effect on i
	++*p;     //adds 1 to j; means *p = *p + 1
}