// 2D Arrays in Java

import java.text.DecimalFormat;

public class Matrices {
    
    public static int NROWS = 4;
    public static int NCOLS = 3;
    
    public static void main(String []args) {
        
        // Declare and allocate matrices
        int [][]matrix0 = new int[NROWS][NCOLS];
        int [][]matrix1 = new int[NROWS][NCOLS];
        int [][]sum     = new int[NROWS][NCOLS];
        
        // Initialize the matrices
        for (int row = 0; row < NROWS; row++) {
            for (int col = 0; col < NCOLS; col++) {
                matrix0[row][col] = row * 10 + col;
                matrix1[row][col] = col * 10 + row;
            }
        }
        
        // Add and multiply the matrices
        sum = addMatrix(matrix0, matrix1);
        
        // Print the matrices
        System.out.println("First Matrix");
        printMatrix(matrix0);
        System.out.println("Second Matrix");
        printMatrix(matrix1);
        System.out.println("Sum of Matrices");
        printMatrix(sum);
    }
    
    // Matrix addition
    private static int[][] addMatrix(int[][] m0, int[][] m1) {

        int [][]sumMatrix = new int[NROWS][NCOLS];
        for (int row = 0; row < NROWS; row++) {
            for (int col = 0; col < NCOLS; col++) {
                sumMatrix[row][col] =
                        m0[row][col] + m1[row][col];
            }
        }   
        return sumMatrix;
    }
    
    // Prints a matrix
    private static void printMatrix(int[][] matrix) {
        
        // Formatter for output
        DecimalFormat fmt = new DecimalFormat("00");
        
        // Double loop
        for (int row = 0; row < matrix.length; row++) {
            for (int col = 0; col < matrix[0].length; col++) {
                System.out.print(fmt.format(matrix[row][col]) + " ");
            }
            System.out.println();
        }
    }
}