# 2017 New Spec

## Question 3

The algorithm represented using pseudo-code in Figure 5 describes a method to find the greatest common factor (GCF) of two whole numbers (integers) entered by the user.

### Figure 5

OUTPUT "Enter a whole number: " INPUT Number1 OUTPUT "Enter another whole number: " INPUT Number2 Temp1 ← Number1 Temp2 ← Number2 WHILE Temp1 ≠ Temp2 IF Temp1 > Temp2 THEN Temp1 ← Temp1 – Temp2 ELSE Temp2 ← Temp2 – Temp1 ENDIF ENDWHILE Result ← Temp1 OUTPUT Result, " is GCF of ", Number1, " and ", Number2

### What you need to do:

**Task 1**

Write a program to implement the algorithm in Figure 5.

**Task 2**

Test the program by showing the result of entering 12 and then 39

### Evidence that you need to provide

Include the following in your Electronic Answer Document:

Your PROGRAM SOURCE CODE for Task 1. **[6 marks]**

SCREEN CAPTURE(S) showing the test described in Task 2. **[1 mark]**