COMP 110 More Arrays

1
COMP 110More Arrays

• Tabitha Peck M.S.
• April 2, 2008
• MWF 3-350 pm
• Philips 367

2
Announcements

• Program 4
• Due April 23 (thats 3 weeks!)
• This is a HARD program
• Start early
• Start early
• Start early

3
Program 4 Demo
4
Questions?
5
Today in COMP 110

• More about arrays
• Info for program 4

6
You have Seen Arrays Before

• import java.util. public class Arguments
  public static void main(String
  args) for(int i 0 i lt
  args.length i)
  System.out.println(argsi)
  
• Build ? Run Arguments

7
Arrays in ClassesInstance Variable

• private int intArray
• public static void setLength(int len)
• intArray new intlen

8
Array of Classes

• Smiley smile new Smiley3

9
Arrays as Arguments

• public void changeArray(int a)
• int len a.length
• alen 25

25
10
Arrays as Return Types

• public float buildArray(int len)
• float ret new floatlen
• for(int i 0 i lt len i)
• reti i1.5
• return ret

11
Types

• int array new int3
• array0 5
• array1 6
• array2 8
• What is the type of array?
• What is the type of array2?

12
Indexed variables as arguments

• public void myMethod(int, Smiley)
• this.myMethod(intArray2, sArray0)
• Read FAQ on p. 440

Cannot change value
Can change smiley
13
Swap
14
2D Arrays

• Int twoD new int34

column
row
15
Selection Sort

• For (index 0 index lt length index)
• Find index of smallest value of array from index
  to length
• Swap values of current index and the index with
  the smallest value

16
Selection Sort
17
Bubble Sort
18
Friday

• Lab 7
• Sorting Algorithms