• Announce
  • Lab #3 Today
  • Quiz on Monday

• The string Member Functions
  string demo = "Monday morning";
  • Length: int length()
demo.length() == 14
  • Substring: string substr(int pos, int len)
demo.substr(7,4) == "morn"
  • Find: int find(string s)
demo.find("y m") == 5 (not found: string::npos )

• Examples Using String Functions (class)

• Member Function vs Free Function
  • int length() is member function of string class
  • int sqrt(int) is not part of any class

• String Example: Yes of No Response
  • What can go wrong when expecting a yes/no response?
  • Look at yesOrNo.cpp
  • What is not tested by this example main()?
  • What is a more practical way to use this function?

• Preconditions and Postconditions for Functions

Chapt 5. Iteration with Programs and Classes

• Iteration (pre-tested)
  • initialization
  • loop test
  • loop body
  • update

• while Loop Syntax

while ( test expression )
{
statement list
}

• While Example blastoff.cpp

• Diamonds are for Fun diamonds.cpp

• More Looping: Math Tables
  formerly got PhD for better tables
  pow1.cpp
pow2.cpp

• The Fence Post Problem

• for Loop Syntax
  

  for(initialization; test expression; update)

  {

  statement list

  }

  • Use where number of iterations is "known"
  • Good for most examples shown previously

• Class: Modify blastoff.cpp

• Problem: Adder Program

  Add an unknown number of numbers

  When to quit

  Sentinel Value

  while or for ?

  
  adder.cpp

• Defining Constants
  const type identifier = value;
  all caps

• Pre-tested and Post-tested Loops

• Iteration (post-tested)
  • initialization
  • loop body
  • update
  • loop test

• do-while Loop Syntax

  do

  {

  statement list

  } while ( test expression )

• Using the do-while Loop
  addwhile.cpp

• Infinite Loops

• break Statement

• Nested Loops multable.cpp
  nesting can be hidden by using function

• Scope of Variables
  • definition
  • braces { }
  • Private Variables
  • Global Variables (XXX)

• Random Numbers & N-sided Dice: Simulations

• Class: dice
  • State
  • Behavior

• Using dice
  roll.cpp

• Class Diagram
  • Public
    • constructor
    • member functions
  • Private
    • member functions
    • data

• Constructors

• The Dice Interface
  dice.h
  "Declaration" not code (not Definition)

• Dice Implementation
  dice.cpp

• Iteration (pre-tested)
  • initialization
  • loop test
  • loop body
  • update

• Dice/While Example roll300.cpp
  modify to use for loop