Computer Science

1. 1.

   A function receives integer x by value, assigns x=x+1 and returns nothing. The caller's variable n was 5. State n after the call and explain why.

   [3 marks] · no calculator
2. 2.

   Distinguish validation from verification for an entered date of birth, giving one example of each.

   [3 marks] · no calculator
3. 3.

   Trace: total=0; FOR i=1 TO 4 inclusive: IF i mod 2=0 THEN total=total+i ELSE total=total-1. Give total after each iteration.

   [3 marks] · no calculator
4. 4.

   A recursive function F(n) returns 1 if n=0, otherwise returns n*F(n-1), for integer n>=0. Trace F(4), and explain the base case's role.

   [3 marks] · no calculator
5. 5.

   A function accepts integer ages from 16 through 120 inclusive. Design a minimal boundary-focused test set that checks both acceptance boundaries and adjacent rejection, plus one distinct type-error case; state expected outcomes.

   [4 marks] · no calculator
6. 6.

   Two tasks both execute read counter; add 1 locally; write counter. Starting at zero, show an interleaving ending at 1 rather than 2, and propose a synchronisation remedy with its scope.

   [4 marks] · no calculator

Original, unofficial practice questions from SubjectScout — not official past-paper questions.