Programming Assignment #4 Solution

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));

}




}

//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 {

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]







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







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




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"};













}




}

//Triple Duplicate Element is : Wilson







Complete the following balls.java program as we discussed at the class (up-down 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;




}




}




}

int x;




int y;

int size;




int speed;

String direction;




Color color;

}