Class 0: Review and Perspective

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Class 0 Review and Perspective
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Class info

• Barry Cohen
• bcohen_at_cs.njit.edu
• Office hours W 315-440F 400-525
• www.cs.njit.edu/bcohen/601
• Text Irvine, C And Object-Oriented Programming
• Recommended Schildt, C the Complete Reference

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Grading

• 35 homework
• 30 midterm
• 35 final

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Homework

• Include the following
• student name
• student ID
• date
• class and section
• homework number
• Homework must be handed in on or before the due
  date. Multiple pages must be stapled together.
• You must hand in source code and program output.
  Programs must compile in VC.

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Honesty policy

• You may discuss class content and assignments
  with others. You may not present someone elses
  work as your own. Any instance of cheating will
  be disciplined under NJIT rules.

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HW 0

• Due Sept 13, 2002
• p 20, problems 1,2,3
• p 54, problem 1

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Life Cycle of a Program

• Specification. Analyze and describe the problem.
• Design. Choose your data structures and
  algorithms.
• Coding. Translate the design into the programming
  language of your choice.
• Debugging. Squash those pesky beasties. Test and
  squash some more.
• Maintenance. More bug fixes. Add more features.
  Make friendlier and more efficient.

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Whats a Good Solution?

• Correctness. Solve the problem thats been posed.
• Robustness. Handle the unexpected.
• Modularity. Make it logical and reusable.
• Clarity. Think clearly. Explain your thinking.
• Can be maintained and extended.

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How to document

• Precondition. Where are you starting from.
• Invariant. What stays the same as you progress.
• Progress. Show youre not going in circles.
• Post condition. Where you need to end up.
• Use asserts.

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Pseudocode

• High level summary
• One line for each idea
• Example 1 Read the initialization files
• Example 2 Perform a topological sort

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Flowcharts

• Make the logic visible.
• Stop or start
• Decide
• Do

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Use Functions

• A function is a unit of code.
• The one-page rule.
• Keep data private.
• Clearly define inputs and outputs.

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Programming Style

• Consistent indentation. Use white space.
• Document. Give yourself credit. Use comments.
• Descriptive names. Follow name conventions.

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Why Document?

• Someone will read it - beginning with you.
• Programs live longer than programmers.
• Tells you where you need to go.

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Quick Review of C

• Data types. int, double, char. C bool
• Data structures. Arrays.

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Control Structures

• if .. else
• for loop
• while loop
• do loop
• switch .. case

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Scope

• Auto
• Declared in function
• Allocated on stack
• Static
• Declared outside function
• Declared as static
• Allocated permanently

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Pass by reference

• In C, you can pass by reference
• Example
• void swap(int a, int b)
• int temp xx yy temp

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Stream I/O

• Stream output
• int n 65
• cout ltlt n
• Stream input
• int n
• cin gtgt n

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Comments

• Two kinds of comments
• /
• This is a multiline comment.
• /
• int n // 1-line comment

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C, C

• C is C with classes
• Class groups object with operations
• Object is instance of a class
• Example class coin
• Attributes value, upside
• Actions flip, getValue