#include <iostream>
#include <cstdlib>
using namespace std;

class function_object {
public:
	bool operator()(int a, int b) const {return a < b;}
};

inline bool f(int a, int b) {return a < b;}

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

	bool b = f(i, j);          //f is a function.
	cout << boolalpha << b << "\n";

	bool (*p)(int, int) = f;   //p is a pointer to a function.
	b = (*p)(i, j);            //Lines 21-22 are two ways to call the ...
	b = p(i, j);               //... function to which p points.
	cout << b << "\n";

	function_object g;
	b = g(i, j);               //b = g.operator()(i, j);
	cout << b << "\n";

	return EXIT_SUCCESS;
}