Consider the C program below.

#include < stdio.h >
int *A, stkTop;
int stkFunc(int opcode, int val)
{
     static int size=0, stkTop=0;
     switch (opcode) {
         case -1: size = val; break;
         case 0: if (stkTop < size) A[stkTop++] = val; break;
         default: if (stkTop) return A[--stkTop];
     }
     return -1;
}
int main()
{
     int B[20]; A = B; stkTop = -1;
     stkFunc (-1, 10);
     stkFunc ( 0, 5);
     stkFunc ( 0, 10);
     printf ("%d\n", stkFunc(1, 0) + stkFunc(1, 0));
}

The value printed by the above program is __________.

Consider the program given below, in a block-structured pseudo-language with lexical scoping and nesting of procedures permitted.

Program main;
  Var . . .

  Procedure A1;
      Var . . .
      Call A2;
  End A1

  Procedure A2;
      Var . . .

      Procedure A21;
        Var . . .
        Call A1;
      End A21

      Call A21;
  End A2

  Call A1;
End main.

Consider the calling chain: Main $$ \to $$ A1 $$ \to $$ A2 $$ \to $$ A21 $$ \to $$ A1
The correct set of activation records along with their access links is given by

Consider the following recursive C function that takes two arguments:

unsigned int foo (unsigned int n, unsigned int r) {
  if (n > 0) return((n % r) + foo(n/r, r));
  else return 0;
}

What is the return value of the function foo when it is called as foo (513, 2)?

Consider the following recursive C function that takes two arguments:

unsigned int foo (unsigned int n, unsigned int r) {
  if (n > 0) return((n % r) + foo(n/r, r));
  else return 0;
}

What is the return value of the function foo when it is called as foo (345, 10)?