Subroutines and Functions Activity

What are two types of subroutine used in programming?

• Variables and Constants

• Functions and Procedures

• Loops and Conditions

• Arrays and Strings

How many parameters can functions and procedures have?

• Zero, one or many

• Three

• One

• Two

Explain the difference between a local and global variables

• Local variables can be changed once declared, globals cannot be changed once declared

• Local variables are declared using the CONSTANT keyword, globals are declared using the VAR keyword

• Local variables are accessible anywhere in the program, globals only within the subroutine

• Local variables are only accessible within the particular function or procedure, globals are accessible anywhere in the program

What are three reasons that you should try to use subroutines where possible?

• To make the program less maintainable, to decompose the code, to make the program more complex

• To reuse code, to make the program less maintainable, to make the program more complex

• To make the program more complex, to increase development time, to make program maintenance harder

• Reuse code, decomposition, more maintainable code

What is one other advantage of using subroutines?

• Subroutines can be stored in a subroutine library and used in different programs if required

• To make the program less maintainable

• To make program maintenance harder

• To make the program more complex

What is output by this program? PROCEDURE changeNum num ← 6 OUTPUT num ENDPROCEDURE #Main program num ← 5 OUTPUT num #call function changenum CALL changeNum OUTPUT num

• Outputs 5, Outputs 5, Outputs 6

• Outputs 5, Outputs 6, Outputs 6

• Outputs 5, Outputs 6, Outputs 5

• Outputs 6, Outputs 5, Outputs 5

What type of data structure is heights? How will the function be called?

• heights is a tuple, The function is called and the result stored with a statement such as: tallest ← CalcMax(pupilHeights)

• heights is an array, The function is called and the result stored with a statement such as: tallest ← CalcMax(pupilHeights)

• heights is a list, The function is called and the result stored with a statement such as: tallest ← CalcMax(pupilHeights)

• heights is a string, The function is called and the result stored with a statement such as: tallest ← CalcMax(pupilHeights)

What are the parameters in the above code? Built-in functions print("Hello") # a procedure to output text input("Type in your name: ") # a function that returns what the user enters random(1,6) # a function that returns an integer between 1 and 6

• "Hello", "Type in your name: ", 6, 1

• "Hello", "Type in your name: ", 1, 6

• "Hello", "Type in your name: ", 2, 5

• "Hello", "Type in your name: ", 3, 4

What is the output from the above function? Explain how it works FUNCTION sum(a:INTEGER, b:INTEGER) RETURNS INTEGER total ← a + b RETURN total ENDFUNCTION answer ← sum(5, 3) OUTPUT answer

• Output: 8, This is a function as it returns a value

• Output: 5, This is a function as it returns a value

• Output: 8, This is a procedure as it doesn’t return anything

• Output: 5, This is a procedure as it doesn’t return anything

Write a function named ‘greatest’ that has three parameters which are numbers The function needs to return the greatest of the three numbers

• FUNCTION greatest(a:INTEGER, b:INTEGER, c:INTEGER) RETURNS INTEGER IF a > b AND a > c THEN RETURN a IF b > a AND b > c THEN RETURN c ELSE RETURN b ENDFUNCTION

• FUNCTION greatest(a:INTEGER, b:INTEGER, c:INTEGER) RETURNS INTEGER IF a > b AND a > c THEN RETURN a IF b > a AND b > c THEN RETURN b ELSE RETURN c ENDFUNCTION

• FUNCTION greatest(a:INTEGER, b:INTEGER, c:INTEGER) RETURNS INTEGER IF a > b AND a > c THEN RETURN c IF b > a AND b > c THEN RETURN a ELSE RETURN b ENDFUNCTION

• FUNCTION greatest(a:INTEGER, b:INTEGER, c:INTEGER) RETURNS INTEGER IF a > b AND a > c THEN RETURN b IF b > a AND b > c THEN RETURN a ELSE RETURN c ENDFUNCTION