Problem Solving, Abstraction, and Stepwise Refinement

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Problem Solving, Abstraction, and Stepwise
Refinement
CS240-Intermediate Programming
Created by Andrew StaugaardModified by Prof.
Martins

• Chaminade University of Honolulu
• Department of Computer Science

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The Programmers Algorithm

• Define the problem.Plan the problem
  solution.Code the program.Test and debug the
  program.Document the program.

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Define the Problem

• The problem must defined in terms of output,
  input, and processing. Look for nouns in the
  problem statement that suggest output and input.
  Look for verbs to suggest processing steps.

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Plan the Solution

• When planning computer programs, algorithms are
  used to outline the solution steps using English
  like statements, called pseudocode. A good
  pseudocode algorithm should be independent of,
  but easily translated into, any formal procedural
  programming language.

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Code the Program

• Coding involves the actual writing of the program
  in a formal programming language. Once a language
  is chosen, the program is written, or coded, by
  translating your algorithm steps into the formal
  language code.

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Debug the Program

• Realize that you have an error.Locate and
  determine the cause of the error.Fix the error.
• Desk-check the program,
• Compile the program.
• Run the program.
• Debug the program using a debugger.

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Document the Program

• The final program documentation is simply the
  recorded result of the problem definition,
  solution planning, coding, testing results,
  debugging results, and user instructions.

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Problem Abstraction

• Abstraction provides for generalization in
  problem solving by allowing you to view a problem
  in general terms, without worrying about the
  details of the problem solution.

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Stepwise Refinement

• Stepwise refinement is the process of gradually
  adding detail to a general problem solution until
  it can be easily coded in a computer language.