1. MIS 222 – Lecture 12
10/9/2003

2. Assignment 11
Demo
8.1.10

3. Arrays Company Profits 1 4000 2 122154 3 55255 4 -564654 5 541818 6
int[] companies = new int[8];
companies[0] = 4000;
companies[1] = ;
companies[2] = 55255;
companies[3] = ;
companies[4] = ;
companies[5] = ;
companies[6] = ;
companies[7] = ;
Company
Profits 1
4000 2
122154 3
55255 4 5
541818 6
781849 7 8
843257
Exact same data types
Similar information

4. Array Literals
int[] companies = {4000, , 55255, , , , , };
enclosed in brackets
separated by commas
String[] letters = {“a”, “b”, “c”};
System.out.println(letters[2]);
System.out.println(letters[3]);

5. Array Literals Example
8.2.1

6. Shallow Copy Array Copying
int[] companies = {4000, , 55255, , , , , };
int[] myComps = companies;
myComps[0] = 1;
System.out.println(companies[0]);
companies
8475
Shallow Copy
myComps
8475 1 2 3 4 5 6 7
4000
122154
55255
541818
781849
843257
8475

7. Deep Copy Array Copying
int[] companies = {4000, , 55255, , , , , };
int[] myComps =new int[companies.length];
System.arraycopy(companies, 0, myComps, 0, companies.length);
myComps[0] = 1;
System.out.println(companies[0]);
companies
8475
Deep Copy 1 2 3 4 5 6 7
4000
122154
55255
541818
781849
843257
8475
myComps
9985 1 2 3 4 5 6 7
4000
122154
55255
541818
781849
843257
9985

8. Arrays as Arguments (to methods)
Average()
int[]
int
8475
companies
4000
122154
55255
541818
781849
843257 1 2 3 4 5 6 7 25

9. Arrays as Arguments Here’s what it looks like: public class Average {
public static void main(String[] args){
double[] stuff = {5,15.5,55.55,1};
double avg = average(stuff);
System.out.println(“average of stuff is “ + avg); }
public static double average(double[] nums){
double total = 0;
for(int i = 0; i < nums.length; i++){
total += nums[i];
return total / num.length;

10. Arrays as Arguments public class Average {
public static void main(String[] args){
double[] stuff = {5,15.5,55.55,1};
double avg = average(stuff);
System.out.println(“the third element is “ + stuff[2]); }
public static double average(double[] nums){
double total = 0;
for(int i = 0; i < nums.length; i++){
total += nums[i];
//malicious code
nums[2] = ;
return total / num.length;

11. Arrays as Arguments public class Average {
public static void main(String[] args){
double[] stuff = {5,15.5,55.55,1};
double avg = average(stuff);
System.out.println(“the third element is “ + stuff[2]); }
public static double average(double[] nums){
//body same as previous slide
stuff
8475
nums 1 2 3
8475 5
15.5
55.55 1
8475

12. Example
8.3.7