Question

Write a Java program that does the following.

a. Declare an integer 2D array with 5 rows and 5 columns.

b. Initialize the array's elements to random integers between 1 and 10 (inclusive).

c. Display all the elements in the 2D array as a table of rows and columns.

d. Display the row index and column index of all the even integers in the 2D array.

e. Display the sum of first row's elements.

Answer 1

//TestCode.java
import java.util.Random;
public class TestCode {
    public static void main(String[] args) {
        Random random = new Random();
        int arr[][] = new int[5][5];

        for(int i = 0;i<arr.length;i++){
            for(int j = 0;j<arr[i].length;j++){
                arr[i][j] = 1 + random.nextInt(10);
            }
        }

        System.out.println("2D array as a table of rows and columns: ");
        for(int i = 0;i<arr.length;i++){
            for(int j = 0;j<arr[i].length;j++){
                System.out.print(arr[i][j]+"\t");
            }
            System.out.println();
        }

        System.out.println("\nRow index and column index of all the even integers in the 2D array: ");
        for(int i = 0;i<arr.length;i++){
            for(int j = 0;j<arr[i].length;j++){
                if(arr[i][j]%2==0){
                    System.out.println("row = "+i+", column = "+j);
                }
            }
        }


        int sum = 0;
        for(int i = 0;i<arr[0].length;i++){
            sum += arr[0][i];
        }
        System.out.println("\nSum of first row's elements: "+sum);

    }
}