#include <stdio.h>                                    /* Fig. 7.28 (adapted) */

void function1( int a );  /* prototypes */
void function2( int b );
void function3( int c );

int choice; /* variable to hold user's choice */
int getChoice() { printf( "Enter a number between 0 and 2; 3 to end: " );
                           scanf( "%d", &choice ); return  choice >= 0 && choice < 3; }

int main() {
   /*@{}@XPCR{initialize array of 3 pointers to functions
      that each take an @CP {int} argument and return @CP {void}} */
   void (*f[ 3 ])( int ) = { function1, function2, function3 };

   while ( getChoice() )
          /*@{}@XPCR{invoke function @CP {f[choice]} and pass @CP {choice} as an argument} */
          (*f[ choice ])( choice );
   printf( "Program execution completed.\n" ); return 0;
}

void function1( int a )
{
   printf( "You entered %d and function1 was called\n\n", a );
}

void function2( int b )
{
   printf( "You entered %d and function2 was called\n\n", b );
}

void function3( int c )
{
   printf( "You entered %d and function3 was called\n\n", c );
}