Problem Solving Recipe

A recipe for solving toy problems

Really read the problem.

• Read it slowly.
• Read it again.
• Think to yourself, "what assumptions are hidden in this problem?" There are ALWAYS assumptions. Ask at least one question about those assumptions.
• If you are working alone (recording a video), just ask yourself, out loud.
• Identify input and outputs.

Outline your approach

• Decide on your core data structure or data type.
• What are the start and end states of that data?
• How does that data "mutate" from start state to end state?
• Outline your state-changing logic in English pseudo-code.
• Re-read it, edit it, make it clear and precise.
• Outline your structure with one or more empty functions (aka stub functions).
• Give those stubs clear names.

Implement carefully, step-by-step.

• Fill in the main function body.
• Stub out helper functions if need be.
• Each function should ideally have a single purpose.
• It should do only one, small thing.
• That one thing is expressed clearly by the function's name.
• Test as you go.
• Each component (or "unit") -- for now, they are functions -- has a clear contract.
• Write an assertion
• Assert what behavior should be true about that component.