void foo (int n, int sum) {
  int k = 0, j = 0;
  if(n==0) return;
  k=n%10; j = n /10;
  sum = sum + k;
  foo(j, sum);
  printf("%d",k);
}
int main () {
  int a = 2048, sum = 0;
  foo(a, sum);
  printf("%d\n", sum);
}

double foo(double); /* Line 1 */
int main () {
  double da, db;
  //input da
  db = foo(da);
}
double foo(double a){
  return a;
}

int (*f)(int *);