/*
 * Looking at pointers to functions
 *
 *    int *p;         # p is pointer to int
 *    (int *)p;       # same
 *    int* p;         # same
 *    
 *    int **(***f)(int**, int);  # very ugly but syntax OK

 *    f is a pointer to a pointer to a pointer to 
 *    a function which returns a pointer to a pointer to 
 *    an int and which takes two arguments, one of which 
 *    is a pointer to a pointer to an int, and one of 
 *    which is an int

 */

#include <stdio.h>


// a function
int f1(int i, int j){
  return 2*i + j;
}

int f2(int i, int j){
  return i + 3*j;
}

void doit_print(int (*func)(int, int), int a, int b){
  int answer = (*func)(a,b);
  printf(" the answer is %b\n", answer);
}

int main(){
  
  doit_print(&f1, 3, 4);  // f1(3,4) and print output
  doit_print(&f2, 3, 4);

  return 0;
}