Chapter 2 Problem Solving, Abstraction, and Stepwise Refinement

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Chapter 2Problem Solving, Abstraction, and
Stepwise Refinement
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Chapter 2

• The Programmers AlgorithmDefine the
  problem.Plan the problem solution.Code the
  program.Test and debug the program.Document the
  program.

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Chapter 2

• Define the ProblemThe 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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Chapter 2

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

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Chapter 2

• Code the ProgramCoding 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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Chapter 2

• Debug the ProgramRealize 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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Chapter 2

• Document the ProgramThe 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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Chapter 2

• Problem AbstractionAbstraction 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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Chapter 2

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