Arrays In Class

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Arrays In Class

• Briana Morrison

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Objectives

• Determine how much you have retained from CS /
  SWE 1301
• Remember arrays!

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Problem 1

• What is an array?

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Short Answers

• Each variable in an array is called a(n)
  _____________________________
• Use a(n) ___________________ to specify the
  position of an item in an array.

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Write some code

• Write a declaration for an array that will hold
  characters.
• Instantiate the array to hold 15 characters.
• Declare and initialize an array of integers to
  hold the values 1-5.

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Array Access

• Complete this chart with code

Element Syntax
Element 0
Element i
Last element
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More code

• Write the code to instantiate an array to hold 3
  Auto objects.
• Why is this code different than an array that
  holds integers or characters?

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Problem code

• Whats wrong with the following code?

double billsBackup new double
6 billsBackup cellBills
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More short answers

• How can you compare two arrays for equality?

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Searching and Sorting

• List two ways to find an item in an array.
• List two ways to sort an array.

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Sorting

• If I have the following
• int array 19, 14, 6, 22, 14, 3, 11, 15
• Do a bubble sort on the array and show all swaps
  and iterations.
• Do a selection sort on the array and show all
  swaps and iterations.
• Do an insertion sort on the array and show all
  swaps and iterations.

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More Code

• Write the code to print each element in an array
  named cellBills, one element per line (assuming
  that cellBills has been instantiated).

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More Code

• Write the code to calculate the total value of
  all elements in an array named cellBills, which
  has previously been instantiated.

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Arrays and Classes

• Can a class have an array for an instance
  variable?
• What things do you have to remember when an array
  contains an array?

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Problems

• Whats wrong with the following code?

class Names private String name new
String5 public String getNames( )
return name public void setName( String
name) this.name name