COMP 1917 Computing 1
Session 2, 2016

Tutorial - Week 13

Presentation Topic for Week 13

1. What will be the value of the variable z after the following code is executed?

   
   int x = 1; 
   int y = 2; 
   int z = 3; 
   if (x < y) { 
       if (y > 4) { 
           z = 5; 
       } else { 
           z = 6; 
       } 
   }     
   
   

2. What will be the value of result after the following code statements are executed?

   
   int nums1[LENGTH] = { 1, -5, 2, 0, 4, 2, -3 };
   int nums2[LENGTH] = { 1, -5, 2, 4, 4, 2, 7 };
   int result = 0;
   int j = 0;
   while (j < LENGTH) {
       if (nums1[j] != nums2[j]) {
           result = result + 1;
       }
       j = j + 1;
   }
   
   

3. What is the purpose or outcome of the following piece of code?

   int number[LENGTH];
   ...
   int result = 0;
   int j = 0;
   while ( j < LENGTH) {
      if (number[j] < 0) {
          result = result + 1;
      }
      j++;
   }
   

4. When the following code is compiled and executed it eventually executes the printf and terminates. What value does it print?

   #include <stdio.h>
   #define NINE 9
   
   int nine (int n);
   int nein (int n);
   int main (int argc, char *argv[]) {
      
      int Nine = 3;
      printf ("%d\n", nine (Nine));
      return !NINE;
   }
   
   int nein (int nein) {
      return ( !(nein == ((NINE*nein) % NINE)) );
   }
   
   int nine (int Nein) {
      int Nine = NINE;
      while (nein (Nine)) {
         Nine += Nein;
         Nine = Nine % NINE;
      }
      return Nine;
   }
   

5. Describe the memory layout of a typical C program. What information can be stored in each of the segments?

6. Consider the following C function prototype:

   int f(int *x, int y);
   

   Which of the following statements is true of argument `x`? What about variable y?

    .[A] it is passed by magic
    .[B] It is passed by copying
    .[C] It is passed by reference
    .[D] It is passed by abstraction
    .[E] None of the above
   

More past papers are available at the following link.