From Computer Science Wiki
Explaining sub-processes[1]

Once you fully understand a problem, you must solve it. Many problems require a decision (for example is one value different, is another value greater, are two values the same, is one of two values true) . The key point here is to pause and fully understand what type of decision(s) you must make to solve the problem.

Please don't start thinking about operators or conditionals yet. Just ask and answer what are the exact decisions I must make to solve this problem?

How to think about decisions[edit]

With gratitude to and permission from Stephen Hughes (Coe College) and Philip East (University of Northern Iowa)[2], The list below is an example of types of conditional questions. You should start thinking about conditions in plain english before you start thinking about operators. When you are thinking about decisions, these words below will help you think about what kind of decision you must make.

  1. Match
  2. Threshold
  3. Range
  4. One-of
  5. Not-match
  6. Not one of
  7. All of
  8. Some of
  9. Eligible

A video to help you understand this[edit]


These standards are used from the IB Computer Science Subject Guide[3]

  • Identify when decision-making is required in a specified situation.
  • Identify the decisions required for the solution to a specified problem.
  • Identify the condition associated with a given decision in a specified problem.
  • Explain the relationship between the decisions and conditions of a system.


  3. IB Diploma Programme Computer science guide (first examinations 2014). Cardiff, Wales, United Kingdom: International Baccalaureate Organization. January 2012.