Unit 8 Homework
Homework Hacks
Create a class for 2D array learning, a new object to test out each method in the main function, and methods to initialize a 2D array with arbitrary values, reverse the 2D array and print out the values, that ask for the input of a position and it returns the corresponding value, and that multiply each value in a row and then adds all the products together.
// class for 2D array
public class twoDArray {
private int[][] numbers;
public twoDArray(){
numbers = new int [3][5];
this.numbers = numbers;
}
// method for initializing 2D array with arbitrary values
public void initValues(){
System.out.println("Initial Array");
Random random = new Random();
for(int i = 0; i < numbers.length;i++){
for(int j = 0; j <numbers[i].length;j++){
numbers[i][j] = random.nextInt(11 - 1) + 1;
System.out.print(numbers[i][j]+" ");
}
System.out.println(" ");
}
}
// method for reversing 2D array and printing out values
public void revArray() {
System.out.println("\nReversed Array");
for(int i = numbers.length-1;i>=0;i--){
for(int j = 0; j <numbers[i].length;j++){
System.out.print(numbers[i][j]+" ");
}
System.out.println(" ");
}
System.out.println("\n");
}
// method that multiplies each value in a row and then adds all the products together
public void productSum() {
int finalProduct = 1;
for(int i = 0;i<numbers.length;i++){
int product = 1;
for(int j = 0; j < numbers[i].length;j++){
product = product * numbers[i][j];
}
System.out.print("When row is: " + i + ", product is: " + product);
System.out.println(" ");
finalProduct += product;
}
System.out.print("The sum of all of the products is: " + finalProduct);
System.out.println("\n");
}
// method that asks for the input of a position and it returns the corresponding value
public void outputArrayValue() {
Scanner myObj = new Scanner(System.in);
System.out.println("Input a row number");
String arrayValue1 = myObj.nextLine();
System.out.println(arrayValue1);
int numArrayValue1 = Integer.parseInt(arrayValue1);
System.out.println("Input a column number");
String arrayValue2 = myObj.nextLine();
System.out.println(arrayValue2);
int numArrayValue2 = Integer.parseInt(arrayValue2);
System.out.println("At that position in the array, the value is: " + numbers[numArrayValue1][numArrayValue2]);
System.out.println("\n");
}
}
// new object to test out each method in the main function
twoDArray anArray = new twoDArray();
anArray.initValues();
anArray.revArray();
anArray.outputArrayValue();
anArray.productSum();