A telephone number with 13 characters is input. The first character is a '+', followed by a 2-digit country code, for example: +20XXXXXXXXXxx where 20 is the country code and x is a digit between 0 and 9 inclusive. The algorithm includes checks for the country codes: 44 for the UK and 20 for Egypt.

Mark scheme

Marking points from the official mark scheme (May/June 2025). The mark or mark type is shown in brackets.

1. [1] (a) Correct input of number
2. [1] (a) Use of substring()
3. [1] (a) ...to extract the correct number
4. [1] (a) Correct use of IF statements/Case statement with matching END IF /END CASE
5. [1] (a) Output of matching locations
6. [1] (a) Output of unknown
7. Example (a): OUTPUT "Please enter a telephone number " INPUT Telephone Value ← SUBSTRING(Telephone, 2, 2) IF Value = "44" THEN OUTPUT "UK" ELSE IF Value = "20" THEN OUTPUT "Egypt" ELSE OUTPUT "Unknown" ENDIF ENDIF
8. [1] (b) Find length of input.
9. [1] (b) Use a suitable loop (repeat/while).
10. [1] (b) Using the correct condition
11. [1] (b) Prompt for a 13-digit telephone number and input number inside loop.