FIRST EXAMINATION IN ENGINEERING
Programme Codes:  ENBDF0002, ENBDF0003,
ENBDF0004, ENBDF0005, ENBDF0008, ENBDF0011

COMP1604 COMPUTER SCIENCE, SUMMER EXAMINATIONS 2003

SOLUTIONS

1.(a) True

  (b) False (e.g. could have run-time errors)

  (c) The most widely used tools for developing algorithms
       are flowcharts and __pseudo-code__ .

  (d) value of w is -3

  (e) value is 1.7321

  (f) exceptional case

  (g) condition is true

  (h) i is 12
      i is 3
      i is 0

  (i) default
      2
      3
      default
      default

  (j) correct answer is (j-2)  it does not return a value

  (k) correct answer is (k-3)  fname() takes 1 argument of
       type pointer-to-double and returns a value of type int.

  (l) result is 19

  (m) correct answer is (m-3)  arr[0]+arr[2]

  (n) False (compiles ok, up to programmer to not access
       memory locations that are not part of the array)

  (o) x[0] is 2.00
      x[1] is 1.00
      x[2] is 0.67
      y[0] is 2
      y[1] is 1
      y[2] is 0

  (p) correct answer is (p-2)  *ptr1 = y;

  (q) x is 5 and y is 5

  (r) True

  (s) vowels=YYYou

  (t) correct answer is (t-1)  open datafile.txt for appending,
       creating the file if it doesn't already exist.


2.(a) int i; /* could be: int i=0; */
      char string[100];
      /* assume string[] is somehow filled with letters, digits, etc */
      i=0;
      while (string[i]!='\0'){
         if ((string[i] >= '0') && (string[i] <= '9')){
            printf("%c", string[i]);
         }
         i++;
      }

  (b) switch(mark){
         case 10:
         case 9:
         case 8:
         case 7: printf("Excellent\n"); break;
         case 6:
         case 5:
         case 4: printf("Satisfactory\n"); break;
         case 3:
         case 2:
         case 1:
         case 0: printf("Fail\n"); break;
         default:
      }

  (c) void nonneg(int array[], int size){
         int i; /* local loop counter */
         for (i=0; i<size; i++){
            if (array[i]<0){
               array[i]=0;
            }
         }
      }


3.(a) LINE 1: scanf("%d", intarr+i);
      LINE 2: total += *(intarr+i);
      LINE 3: printf("sum of inputs is %d, first input was %d,
       last input was %d\n", total, *intarr, *(intarr+3));

  (b)(i) After executing this program, the file output.dat
          contains __2,5,__ .

     (ii) #include <stdio.h>
          void main(void)
          {
             FILE *fptr1, *fptr2;
             int inp;
             fptr1 = fopen("input2.dat", "r");
             fptr2 = fopen("output2.dat", "w");
             while (fscanf(fptr1, "%d", &inp)==1){
                if ((inp%2)==0){
                   fprintf(fptr2, "%d,", inp);
                }
             }
             fclose(fptr1);
             fclose(fptr2);
          }