Nomor 2

package nomor2;

public class Nomor2
{
    public static void main(String[] args)
    {
        int[][] arr = {{1,0,0,0}, {0,1,0,0}, {0,0,1,0}, {0,0,0,1}};
        int countOtherNum = 0;
        int countOne = 0;

        //Print array
        for(int i=0;i<arr.length;i++)
        {
            for(int j=0;j<arr[0].length;j++)
            {
                System.out.print(arr[i][j] + " ");
            }

            System.out.println();
        }

        //Check if the matrix is identity matrix
        for(int i=0;i<arr.length;i++)
        {
            for(int j=0;j<arr[0].length;j++)
            {
                if(j != i)
                {
                    if(arr[i][j] != 0)
                    {
                        countOtherNum++;
                    }
                } else
                {
                    if(arr[i][j] == 1)
                    {
                        countOne++;
                    }
                }
            }
        }

        if(countOne == arr.length && countOtherNum == 0)
        {
            System.out.println("Matriks identitas");
        } else
        {
            System.out.println("Bukan matriks identitas");
        }
    }
}