Basic C Programming

1
Basic C Programming
Review C Programming Elements, Expressions,
Control Flow, Functions, Classes
2
Writing a C Program ( 1.7)

• There are 3 fundamental steps to writing a C
  program
• Design
• Coding
• Testing and Debugging

3
Design ( 1.7.1)

• Perhaps most important step!
• Determine classes
• how they will interact
• data each will store
• actions each will perform

4
Class Design Rules of Thumb ( 1.7.1)

• Responsibilities Divide the work into different
  actors
• each with a different responsibility
• describe responsibilities using action verbs
• actors will form the classes
• Independence Keep work of classes as independent
  as possible
• Behaviors Define behaviors of each class
  carefully and preciselythese will define member
  functions (the set of behaviors may be called a
  protocol).

5
Coding ( 1.7.2)

• Once design phase completed, create actual code
  for the classes (using integrated development
  environment (IDE) like Borland CBuilder).
• Compile into working code
• fix any identified syntax errors
• Run program!

6
Readability and Style ( 1.7.2)

• Programs should be easy to read and understand
• Use meaningful names for identifiers.
• Can be read aloud and reflect the action,
  responsibilty, or data
• capitalize first letter unless for a variable or
  method
• Date Vector identify classes
• isFull() studentName identify a member
  function variable
• Use named constants and enumerations
• Indent statement blocks.
• Organize each class in a consistent order.
• private properties
• private/protected member functions
• public member functions
• Use comments that add meaning and explain
  confusing constructs.

7
Testing Debugging ( 1.7.3)

• Testing
• process of verifying the correctness of program
• Debugging
• process of tracking execution of program and
  discovering errors in it
• Most time-consuming activity in program
  development!

8
Testing ( 1.7.3)

• A careful testing plan is essential.
• Often impossible to verify correctness over all
  possible inputs
• Select a representative subset of test values
• Method coverage
• Every method tested at least once
• Statement coverage (better)
• Every statement executed at least once
• Check special cases.

9
Testing Arrays ( 1.7.3)

• For example, suppose you are testing a method
  that sorts an array of integers.
• Test with an empty array
• Test with an array of length 1
• Test when all elements of the array are equal
• Test when array already sorted
• Test when array in reverse order
• Also with arrays,
• Test that boundary/end values are handled
  properly
• Test with fixed values as well as randomly
  generated/user defined values

10
Debugging ( 1.7.3)

• Possible techniques
• Use print statements (cout ltlt x) to track
  variable values during execution
• simplest technique
• problem these statements must be deleted or
  commented out later before program could be
  executed as desired
• Use a debugger
• better approach
• a specialized environment for controlling and
  monitoring program execution
• insert breakpoints within codeexecution stops at
  each, and current values of variables can be
  observed
• Investigate with Borland C Builder