Matrices

import java.util.Scanner;
class Matrices
{
	private static int i,j;
	private static void input(int[][] arr)
	{
		Scanner sc=new Scanner(System.in);
		for(i=0;i<3;i++)
		{
			System.out.print("Row "+(i+1)+": ");
			for(j=0;j<3;j++)
				arr[i][j]=sc.nextInt();
		}
	}
	private static void display(int[][] arr)
	{
		for(i=0;i<3;i++)
		{
			for(j=0;j<3;j++)
				System.out.print(arr[i][j]+"\t");
			System.out.println();
		}
	}
	public static void main(String[] args)
	{
		//creating all arrays required
		int a[][]=new int[3][3];
		int b[][]=new int[3][3];
		int sum[][]=new int[3][3];
		int pro[][]=new int[3][3];
		//taking input into two matrices
		System.out.println("Enter the elements of the first 3x3 matrix");
		input(a);
		System.out.println("Enter the elements of the second 3x3 matrix");
		input(b);
		//print both matrices with user input
		System.out.println("Matrix I:");
		display(a);
		System.out.println("Matrix II:");
		display(b);
		//adding the two matrices
		for(i=0;i<3;i++)
			for(j=0;j<3;j++)
				sum[i][j]=a[i][j]+b[i][j];
		System.out.println("Matrix Addition I+II:");
		display(sum);
		//multiplying the two matrices, a[][]*b[][]
		int k;
		for(i=0;i<3;i++)
			for(j=0;j<3;j++)
				for(k=0;k<3;k++)
					pro[i][j]+=a[i][k]*b[k][j];
		System.out.println("Matrix Multiplication I*II:");
		display(pro);
	}
}