Question

Please write this in JAVA ONLY.

Write a method with a void return value that inverts all the elements of a two-dimensional array of booleans (true becomes false and false becomes true).

Include code to test your method. Your output should show all the values of the array prior to inverting them and afterwards.

Answer 1

BooleanArrayTest.java

import java.util.Scanner;

public class BooleanArrayTest {

   public static void main(String[] args) {
       Scanner scan = new Scanner(System.in);
       System.out.println("Enter the number of rows: ");
       int rows = scan.nextInt();
       System.out.println("Enter the number of columns: ");
       int cols = scan.nextInt();
       boolean b[][] = new boolean[rows][cols];
       for(int i=0; i<rows; i++){
           for(int j=0; j<cols; j++){
               System.out.print("Enter value: ");
               b[i][j] = scan.nextBoolean();
           }
       }
       System.out.println("Before inverting, Array elements are: ");
       displayArray(b);
       inverts(b);
       System.out.println("After inverting, Array elements are: ");
       displayArray(b);
   }
   public static void inverts (boolean b[][]){
       for(int i=0; i<b.length; i++){
           for(int j=0; j<b[i].length; j++){
               b[i][j] = !b[i][j];
           }
       }
   }
   public static void displayArray(boolean b[][]){
       for(int i=0; i<b.length; i++){
           for(int j=0; j<b[i].length; j++){
               System.out.print(b[i][j]+" ");
           }
           System.out.println();
       }
      
   }

}

Output:

Enter the number of rows: 3 Enter the number of columns: 3 Enter value: true Enter value: true Enter value: false Enter value: false Enter value: false Enter value: true Enter value: true Enter value: false Enter value: false Before inverting, Array elements are: true true false false false true true false false After inverting, Array elements are: false false true true true false false true true