Java program to add or sum two matrices with example

• Given two matrices in Java.
• Write a program two add matrices.
• Two matrices can be added only if they have the same dimension.
  • i.e. two matrices must have the same number of rows and columns.
• Addition is accomplished by adding respective elements of each matrix.

Example to add two matrices in java

Matrix A =    [ {1  2 3}

                {4  5 6}

                {7 8 9} ]


Matrix B =      [ {11  12 13}

                 {14  15 16}

                 {17 18 19} ]


Sum (A + B) = [ {1+11  2 +12 3+13}

                {4+14  5 +15 6+16}

                {7+17  8 +18 9+19} ]


Sum (A + B) = [ {12  14 16 }

                {18  20 22}

                {24  26 28} ]

Program to add or sum two matrices in Java

package org.learn.beginner.matrices;

import java.util.Arrays;

public class AddTwoMatrices {

    private static void sumOfMatrices(int[][] a, int[][] b) {

        System.out.println("Matrix A :" + Arrays.deepToString(a));
        System.out.println("Matrix B :" + Arrays.deepToString(b));
        
        int row = a.length;
        int col = a[0].length;

        int[][] sum = new int[row][col];
        int iRow = 0, iCol = 0;

        while (iRow < row) {

            while (iCol < col) {
                sum[iRow][iCol] = a[iRow][iCol] + b[iRow][iCol];
                iCol++;
            }
            iCol = 0;
            iRow++;
        }

        System.out.println("Sum (A+B) :" + Arrays.deepToString(sum));
    }

    public static void main(String[] args) {
        int[][] A = {{1, 2, 3},

                    {4, 5, 6},

                    {7, 8, 9}};

        int[][] B = {{11, 12, 13},

                    {14, 15, 16},

                    {17, 18, 19}};

        sumOfMatrices(A, B);
    }
}

Output: Sum of two matrices in Java

Matrix A :[[1, 2, 3], [4, 5, 6], [7, 8, 9]]
Matrix B :[[11, 12, 13], [14, 15, 16], [17, 18, 19]]
Sum (A+B) :[[12, 14, 16], [18, 20, 22], [24, 26, 28]]