Assignment #4 Array structures and class

Programming Assignment #4

This assignment focuses on array structures and class. Be sure to include a short comment at the beginning
of your program as well as a short comment for each method describing what it does. For this assignment
you are limited to the language features in Chapters 1-7 shown in lecture or the textbook. You have to
submit 10 java files. Do not change name of classes. (q1~q9: 2points each(no partial points), q10: 7Points)

1. Write a Java program to calculate average value of an array elements.
public class ex1AverageValue {
public static void main(String[] args) {
int[] numbers = new int[]{10, 20, 30, 40, -50, 60, -70};
System.out.println("Average value of the array elements is : " + average);
}
}
// Average value of the array elements is : 5.0
2. Write a Java program to find the index of an array element.
public class ex2FindIndex {
public static int findIndex (int[] my_array, int t) {
}
public static void main(String[] args) {
int[] my_array = new int[] {25, 10, 55, 65, 36, 92, 77, 8, 13, 79};
System.out.println("Index position of 55 is: " + findIndex(my_array, 55));
System.out.println("Index position of 13 is: " + findIndex(my_array, 13));
}
}
//Index position of 55 is: 2
//Index position of 13 is: 8
3. Write a Java program to copy an array by iterating the array.
import java.util.Arrays;
public class ex3CopyArray {
public static void main(String[] args) {
int[] my_array = new int[]{25, 10, 55, 65, 36, 92, 77, 8, 13, 79};
int[] new_array = new int[10];
System.out.println("Source Array : "+Arrays.toString(my_array));

System.out.println("New Array: "+Arrays.toString(new_array));
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}
}
//Source Array : [25, 10, 55, 65, 36, 92, 77, 8, 13, 79]
//New Array: [25, 10, 55, 65, 36, 92, 77, 8, 13, 79]
4. Write a Java program to insert an element (specific position) into an array.
import java.util.Arrays;
public class ex4Insert {
public static void main(String[] args) {

int[] my_array =new int[] {25, 10, 55, 65, 36, 92, 77, 8, 13, 79};
// Insert an element in 3rd position of the array (index-3, value-12)
int Index_position = 3;
int newValue = 12;
System.out.println("Original Array : "+Arrays.toString(my_array));

System.out.println("New Array: "+Arrays.toString(my_array));
}
}
//Original Array : [25, 10, 55, 65, 36, 92, 77, 8, 13, 79]
//New Array: [25, 10, 55, 12, 65, 36, 92, 77, 8, 13]
5. Write a Java program to find the maximum and minimum value of an array.
import java.util.Arrays;
public class ex5MinMax {
static int max;
static int min;
public static void max_min(int my_array[]) {
}

public static void main(String[] args) {
int[] my_array = {25, 10, 55, 65, 36, 92, 77, 8, 13, 79};
max_min(my_array);
System.out.println(" Original Array: "+Arrays.toString(my_array));
System.out.println(" Maximum value for the above array = " + max);
System.out.println(" Minimum value for the above array = " + min);
}
}
//Original Array: [25, 10, 55, 65, 36, 92, 77, 8, 13, 79]
//Maximum value for the above array = 92
//Minimum value for the above array = 8
6. Write a Java program to reverse an array of integer values.
import java.util.Arrays;
public class ex6Reverse {
public static void main(String[] args){
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int[] my_array1 = {2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018,
2019};
System.out.println("Original array : "+Arrays.toString(my_array1));
System.out.println("Reverse array : "+Arrays.toString(my_array1));
}
}
//Original array : [2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019]
//Reverse array : [2019, 2018, 2017, 2016, 2015, 2014, 2013, 2012, 2011, 2010]
7. Write a Java program to find the duplicate values of an array of integer
values.
import java.util.Arrays;
public class ex7DuplicateValue {
public static void main(String[] args)
{
int[] my_array = {1, 2, 3, 3, 4, 5, 6, 2};


}
}
//Duplicate Element : 2
//Duplicate Element : 3

8. Write a Java program to find the duplicate values of an array of string
values.
public class ex8DuplicateString {
public static void main(String[] args)
{
String[] my_array = {"Wilson", "Sherman", "Lynch", "Chancellor", "Graham",
"Wilson", "Lynch"};

}
}
//Duplicate Element is : Wilson
//Duplicate Element is : Lynch
9. Write a Java program to find the TRIPLE duplicate values of an array of
string values.
public class ex9TripleDuplicateString {
public static void main(String[] args)
{
String[] my_array = {"Wilson", "Sherman", "Lynch", "Wilson", "Graham",
"Wilson", "Lynch"};

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}
}
//Triple Duplicate Element is : Wilson
10. Complete the following balls.java program as we discussed at the class (updown only). You have to use the class movingObject.
import java.awt. * ; import java.util. * ;
public class balls {
public static int width = 800; public static int height = 600;
public static int howMany = 20; public static int ballSizeMax = 70;
public static
public static void main(String[] args) {
DrawingPanel panel = new DrawingPanel(width, height);
panel.setBackground(Color.LIGHT_GRAY);
Graphics g = panel.getGraphics();
getInitialStatus();
while (true) {
for (int i = 0; i < howMany; i++) {
g.setColor(
}
panel.sleep(50);
g.clearRect(0, 0, width, height);
}
}
public static void getInitialStatus() {
Random rand = new Random();
for (int i = 0; i < howMany; i++) {
ball[i] = new movingObject();
ball[i].size=rand.nextInt(ballSizeMax) + 10;
}
}
public static Color getColor() {
return myColor;
}
}
}
class movingObject {
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int x;
int y;
int size;
int speed;
String direction;
Color color;
}