#include "stdio.h"

inline void square ( int a ) { printf ( "The square of %d is %d\n", a, a * a ) ; }
inline void cube ( int a ) { printf ( "The cube of %d is %d\n", a, a * a * a ) ; }
inline void fourthpower ( int a ) { printf ( "The fourth power of %d is %d\n", a, a * a * a * a ) ; }

void ( * functionpointers [ 3 ] ) ( int ) ;
/*
the above line declares an array called functionpointers that has three ( 3 ) elements which are all pointers ( * ) to functions which take a single integer as parameter ( int ) and return nothing ( void ) and do not modify the contents of the class in anyway ( const )
*/

void executefunction ( int functionnumber, int inputforfunction )
{
	if ( functionnumber < 0 || functionnumber > 2 ) return ;
	( * functionpointers [ functionnumber ] ) ( inputforfunction ) ;
	// this line calls the function which is pointed ( * ) to by the functionnumber-th element of the functionpointers array which is a member of the object pointed to by the current object pointer ( this ) and passes the function the value of the variable inputforfunction as a parameter
}

int main ( void )
{
	functionpointers [ 0 ] = & square ;
	functionpointers [ 1 ] = & cube ;
	functionpointers [ 2 ] = & fourthpower ;
	
	int count ;
	for ( count = 0; count < 3; count ++ )
		executefunction ( count, 2 ) ;
}