5.1 An algorithm is a step by step breakdown to solving a problem - NSC Information Technology - Question 5 - 2021 - Paper 2

Algorithms should not be language specific because they are designed to be understood and implemented in various programming languages. This universality allows for greater flexibility and applicability across different contexts.

To enhance the readability of the code, it can be indented properly, add line spacing or blank lines where appropriate, and include comments to explain the functionality of different sections.

(a) This is a logical error because the variable iSum is local to the displayAnswer procedure and is not correctly assigned before it is used.

(b) Two reasons why the sum is displayed as 0:

1. The variable iSum in displayAnswer is not initialized; it's declared but remains empty (default to 0).
2. The iSum in the displayAnswer procedure is a different variable from the iSum in the btnCalculateClick procedure, leading to a scope issue.

The line should be completed with the following code:

 iRandom := random(31) + 10;

(a) The correct option is:

(iii) if (iRandom MOD 2 <> 0) then

(b) The statement inc(iCountOdd) should be placed at line:

(ii) 8.

(c) The correct replacement will be:

(iii) Repeat Until iCountOdd = 15;

For variable X, the suitable data type is Integer since the result of Floor(80/12*2) will always yield an integer value.

For variable Y, the most suitable data type is Real or Double, as the Sqr function involves square root operations, which can produce non-integer results.

(a) The positive sign (+) indicates public access to a method or variable, meaning it can be accessed from outside the class. The negative sign (-) indicates private access, meaning it can only be accessed from within the class.

(b) The instance fields/attributes should be declared with the negative sign (-) to restrict access from outside the class and prevent unintended changes to the object's state.

One procedure in the UML diagram is setContactNumber(ContactNumber:String); which is used to set the contact number of the staff.

To complete the algorithm, we can add a loop that calculates the Fibonacci sequence as follows:

 for i from 1 to iNumTerms - 2 do
 begin
   iTerm3 ← iTerm1 + iTerm2;
   sLine ← sLine + ' ' + iTerm3;
   iTerm1 ← iTerm2;
   iTerm2 ← iTerm3;
 end;
 display sLine;