Analysing the problem

The first step of problem solving is to understand the problem thoroughly before attempting any solution. This sounds obvious, but skipping it has a real cost: if we are unclear about what actually needs to be solved, we can spend effort building a program that, when finished, simply does not serve the purpose it was meant for.

What analysing involves

Analysing a problem means reading the problem statement slowly and carefully, and from it:

• listing the principal components of the problem — the main parts or aspects the solution has to deal with, and
• deciding the core functionalities that the solution must provide — what the program absolutely has to be able to do.

The pay-off: knowing inputs and outputs

A careful analysis answers two questions that shape everything built afterwards:

• What inputs should the program accept? — the data the user or environment will supply.
• What outputs should it produce? — the results the program must deliver back. …