Finding the entrywise sum of two matrices.

Here’s a Java program that finds the entrywise sum of two matrices:

  import java.util.Arrays;

   public class MatrixSum {

    public static void main(String[] args) {

        int[][] matrix1 = {

            {1, 2, 3},

            {4, 5, 6},

            {7, 8, 9}

        };

        int[][] matrix2 = {

            {9, 8, 7},

            {6, 5, 4},

            {3, 2, 1}

        };

        int[][] sum = findMatrixSum(matrix1, matrix2);

       
        System.out.println("Matrix 1:");

        printMatrix(matrix1);

        System.out.println("Matrix 2:");

        printMatrix(matrix2);

        System.out.println("Sum:");

        printMatrix(sum);

    }

    public static int[][] findMatrixSum(int[][] matrix1, int[][] matrix2) {

        int rows = matrix1.length;

        int columns = matrix1[0].length;

        int[][] sum = new int[rows][columns];

        for (int i = 0; i < rows; i++) {

            for (int j = 0; j < columns; j++) {

                sum[i][j] = matrix1[i][j] + matrix2[i][j];

            }

        }

        return sum;

    }

  
    public static void printMatrix(int[][] matrix) {

        for (int[] row : matrix) {

            System.out.println(Arrays.toString(row));

        }

        System.out.println();

    }

}

This program defines a `findMatrixSum` function that takes two matrices as input and returns their entrywise sum. The `main` function demonstrates the usage of this function by creating two matrices, finding their sum, and printing the matrices and their sum to the console. The `printMatrix` function is a helper function used to print the matrices in a readable format.

When you run this program, it will output:

Matrix 1:

[1, 2, 3]

[4, 5, 6]

[7, 8, 9]

Matrix 2:

[9, 8, 7]

[6, 5, 4]

[3, 2, 1]

Sum:

[10, 10, 10]

[10, 10, 10]

[10, 10, 10]

In the sum matrix, each element is the sum of the corresponding elements from matrix 1 and matrix 2.