2.1 Algorithms (Past Questions)

There is a subroutine, HEX(), that takes a denary number between 10 and 15 and returns the corresponding hexadecimal number. E.g. HEX(10) would return "A", HEX(15) would return "F".

Write an algorithm, using the subroutine HEX(), to convert any whole decimal number between 0 and 255 into a 2 digit hexadecimal number.

The image contains an example answer.

There were four marks available:

- Taking a number as input

- Using HEX subroutine correctly

- Calculating Digit 1

- Calculating Digit 2

Which line(s) of code earned mark: Taking a number as input

• INPUT decimal

• digitl = decimal DIV 16

• IF digitl>=10 THEN

  ...digit1 = HEX(digit1)

  
  

  IF digit2>=10 THEN

  ...digit2=HEX(digit2)

• digit2 = decimal - (digit1*16)

There is a subroutine, HEX(), that takes a denary number between 10 and 15 and returns the corresponding hexadecimal number. E.g. HEX(10) would return "A", HEX(15) would return "F".

Write an algorithm, using the subroutine HEX(), to convert any whole decimal number between 0 and 255 into a 2 digit hexadecimal number.

The image contains an example answer.

There were four marks available:

- Taking a number as input

- Using HEX subroutine correctly

- Calculating Digit 1

- Calculating Digit 2

Which line(s) of code earned mark: Using HEX subroutine correctly

• INPUT decimal

• digitl = decimal DIV 16

• IF digitl>=10 THEN

  ...digit1 = HEX(digit1)

  
  

  IF digit2>=10 THEN

  ...digit2=HEX(digit2)

• digit2 = decimal - (digit1*16)

There is a subroutine, HEX(), that takes a denary number between 10 and 15 and returns the corresponding hexadecimal number. E.g. HEX(10) would return "A", HEX(15) would return "F".

Write an algorithm, using the subroutine HEX(), to convert any whole decimal number between 0 and 255 into a 2 digit hexadecimal number.

The image contains an example answer.

There were four marks available:

- Taking a number as input

- Using HEX subroutine correctly

- Calculating Digit 1

- Calculating Digit 2

Which line(s) of code earned mark: Calculating Digit 1

• INPUT decimal

• digitl = decimal DIV 16

• IF digitl>=10 THEN

  ...digit1 = HEX(digit1)

  
  

  IF digit2>=10 THEN

  ...digit2=HEX(digit2)

• digit2 = decimal - (digit1*16)

There is a subroutine, HEX(), that takes a denary number between 10 and 15 and returns the corresponding hexadecimal number. E.g. HEX(10) would return "A", HEX(15) would return "F".

Write an algorithm, using the subroutine HEX(), to convert any whole decimal number between 0 and 255 into a 2 digit hexadecimal number.

The image contains an example answer.

There were four marks available:

- Taking a number as input

- Using HEX subroutine correctly

- Calculating Digit 1

- Calculating Digit 2

Which line(s) of code earned mark: Calculating Digit 2

• INPUT decimal

• digitl = decimal DIV 16

• IF digitl>=10 THEN

  ...digit1 = HEX(digit1)

  
  

  IF digit2>=10 THEN

  ...digit2=HEX(digit2)

• digit2 = decimal - (digit1*16)

Johnny is writing a program to create usernames. The first process he has developed is shown in the flowchart in Fig. 1.

[Start]

↓

[Input firstname]

↓

[Input surname]

↓

[name = LEFT(firstName, 3)]

↓

[username = name + left(Surname,2)]

↓

[OUTPUT username]

↓

[Stop]

For example, using the process in Fig. 1, Tom Ward's user name would be TomWa.

State, using the process in Fig. 1, the username for Rebecca Ellis.

• RebEl

• EllRe

• ElReb

• ReEll

Johnny has updated the process used to create usernames as follows:

If the person is male, then their username is the last 3 letters of their surname and the first 2 letters of their first name.

If the person is female, then their username is the first 3 letters of their first name and the first 2 letters of their surname.

What would be the username for a male called Fred Biscuit using the updated process?

• UitFr

• FreBi

• FrUit

• BiFre

Johnny has updated the process used to create usernames as follows:

If the person is male, then their username is the last 3 letters of their surname and the first 2 letters of their first name.

If the person is female, then their username is the first 3 letters of their first name and the first 2 letters of their surname.

Write an algorithm for Johnny to output a username using the updated process.

An example answer can be seen in the image.

There were six marks available:

- Taking firstname, surname and gender as input

- Checking IF gender is male / female (using appropriate selection)

- For male ...Generating last 3 letters of surname using appropriate string manipulation

- ...Generating first 2 of letters of firstname and adding to previous

- For female.... correctly calculating as before

- Correct concatenation and output

Which line(s) earned the mark: - Taking firstname, surname and gender as input

• input firstname, surname, gender

• if gender = "Male" then

• else

• ...username = RIGHT(surname, 3) + LEFT(firstname,2)

• ...username = LEFT (firstname,3) + LEFT(surname,2)

Johnny has updated the process used to create usernames as follows:

If the person is male, then their username is the last 3 letters of their surname and the first 2 letters of their first name.

If the person is female, then their username is the first 3 letters of their first name and the first 2 letters of their surname.

Write an algorithm for Johnny to output a username using the updated process.

An example answer can be seen in the image.

There were six marks available:

- Taking firstname, surname and gender as input

- Checking IF gender is male / female (using appropriate selection)

- For male ...Generating last 3 letters of surname using appropriate string manipulation

- ...Generating first 2 of letters of firstname and adding to previous

- For female.... correctly calculating as before

- Correct concatenation and output

Which line(s) earned the mark: - Checking IF gender is male / female (using appropriate selection)

Answers: 2

• input firstname, surname, gender

• if gender = "Male" then

• else

• ...username = RIGHT(surname, 3) + LEFT(firstname,2)

• ...username = LEFT (firstname,3) + LEFT(surname,2)

Johnny has updated the process used to create usernames as follows:

If the person is male, then their username is the last 3 letters of their surname and the first 2 letters of their first name.

If the person is female, then their username is the first 3 letters of their first name and the first 2 letters of their surname.

Write an algorithm for Johnny to output a username using the updated process.

An example answer can be seen in the image.

There were six marks available:

- Taking firstname, surname and gender as input

- Checking IF gender is male / female (using appropriate selection)

- For male ...Generating last 3 letters of surname using appropriate string manipulation

- ...Generating first 2 of letters of firstname and adding to previous

- For female.... correctly calculating as before

- Correct concatenation and output

Which of the marks did the following line earn?

...username = RIGHT(surname, 3) + LEFT(firstname,2)

Answers: 3

• For male ...Generating last 3 letters of surname using appropriate string manipulation

• ...Generating first 2 of letters of firstname and adding to previous

• For female.... correctly calculating as before

• .Correct concatenation

• Output

Johnny has updated the process used to create usernames as follows:

If the person is male, then their username is the last 3 letters of their surname and the first 2 letters of their first name.

If the person is female, then their username is the first 3 letters of their first name and the first 2 letters of their surname.

Write an algorithm for Johnny to output a username using the updated process.

An example answer can be seen in the image.

There were six marks available:

- Taking firstname, surname and gender as input

- Checking IF gender is male / female (using appropriate selection)

- For male ...Generating last 3 letters of surname using appropriate string manipulation

- ...Generating first 2 of letters of firstname and adding to previous

- For female.... correctly calculating as before

- Correct concatenation and output

Which of the marks did the following line earn?

print (username)

Answers: 1

• For male ...Generating last 3 letters of surname using appropriate string manipulation

• ...Generating first 2 of letters of firstname and adding to previous

• For female.... correctly calculating as before

• .Correct concatenation

• Correct Output