Problem solving/programming

Question 1

subroutine benefits

Answer 1

easier to read
- there are fewer long blocks of code to understand
more efficient
- blocks of code can be used once and re-written many times
more reliable
- each subroutine can be individually tested to make sure it works

Question 2

parametres

Answer 2

• special variables used to pass values into a subroutine

Question 3

arguments

Answer 3

• the actual values that are passed in
• (through the parameter)

Question 4

local variable

Answer 4

• a variable defined within a subroutine
• has a local scope
• can only be accessed within that subroutine

Question 5

global variable

Answer 5

• variable can be made global by adding the ‘global’ keyword before it when first used
• may be accessed by any part of the whole program

Question 6

passing By Reference

Answer 6

• function receives memory location of the data
• will make changes to the original variable
• will overwrite data in the original variable
• will keep the changes after the function ends

Question 7

passing By Value

Answer 7

• function receives a COPY of the variable
• will not overwrite the data in the original variable
• will not keep the changes after the function ends

Question 8

global benefits over local

Answer 8

• don’t need to return a value
• can be accessed from anywhere in the program
• variable doesn’t need passing as a parameter

Question 9

global drawbacks over local

Answer 9

• increases memory usage (held in memory until full program execution is over)

Question 10

benefits of using reusable components

Answer 10

• reduced testing requirements
• saves time from having to write the same algorithm repeatedly