# Find product of Each Row and Column in Java

In Java, Array is an object. It is a non-primitive data type which stores values of similar data type. The matrix in java is nothing but a multi-dimensional array which represents multiple rows and columns.

Here we have given a matrix which contains set of elements and as per the problem statement we have to find the product of each row elements and columns elements.

In this article we will see, how it can be done by using Java programming language.

## To show you some instances

### Instance-1

Given matrix =

21 	22	23
24	25	26
27	28	29

• Product of each row −

• The product of the row-1 is: 10626

• The product of the row-2 is: 15600

• The product of the row-3 is: 21924

• Product of each column −

• The product of the column-1 is: 13608

• The product of the column-2 is: 15400

• The product of the column-3 is: 17342

### Instance-2

Given matrix =

9 	2	2	4
1	7	2	6
2	2	4	3
1	4	7	8

• Product of each row −

• The product of the row 1 is: 144

• The product of the row 2 is: 84

• The product of the row 3 is: 48

• The product of the row 4 is: 224

• Product of each column −

• The product of the column 1 is: 18

• The product of the column 2 is: 112

• The product of the column 3 is: 112

• The product of the column 4 is: 576

### Instance-3

Given matrix =

1 	2	3
4	5	6
7	8	9

• Product of each row −

• The product of the row is: 6

• The product of the row is: 120

• The product of the row is: 504

• Product of each column −

• The product of the column 1 is: 28

• The product of the column 2 is: 80

• The product of the column 3 is: 162

### Algorithm

• Step-1 − Declares and initializes a 2D matrix called inputMatrix.

• Step-2 − Loop through each row of the matrix and calculates the product of the elements in each row. The product of each row is then printed to the console.

• Step-3 − Repeats the same logic for columns and calculates the product of the elements in each column.

• Step-4 − The product of each column is then printed to the console with a different message.

### Syntax

The Matrix.length method in Java returns the length of the given matrix.

Below refers to the syntax of it −

inputMatrix.length


where, ‘inputMatrix’ refers to the given matrix.

## Multiple Approaches

We have provided the solution in different approaches.

• By Using Static Initialization of Matrix Elements

• By Using User Defined Method

Let’s see the program along with its output one by one.

## Approach-1: By Using Static Initialization of Matrix Elements

In this approach, matrix elements will be initialized in the program. Then as per the algorithm calculate the product of elements of the rows and columns of that matrix.

### Example

public class Main {
public static void main(String[] args) {

//declare and initialized a 2d matrix
int[][] inputMatrix = {{1, 2, 3}, {1, 2, 3}, {1, 2, 3}};
System.out.println("Product of each row:");

//initiate the loop to find the rows product values
for (int[] r : inputMatrix) {
int prod = 1;
for (int value : r) {
prod *= value;
}
System.out.println("The product of the row is: " + prod);
}
System.out.println("\nProduct of each column:");

//initiate the loop to find the columns product values
for (int a = 0; a < inputMatrix[0].length; a++) {
int prod = 1;
for (int b = 0; b < inputMatrix.length; b++) {
prod *= inputMatrix[b][a];
}
System.out.println("The product of the column " + (a + 1) + " is: " + prod);
}
}
}


### Output

Product of each row:
The product of the row is: 6
The product of the row is: 6
The product of the row is: 6

Product of each column:
The product of the column 1 is: 1
The product of the column 2 is: 8
The product of the column 3 is: 27


## Approach-2: By Using User Defined Method

In this approach, matrix elements will be initialized in the program. Then call a user defined method by passing the matrix as parameter and inside method as per the algorithm calculate the product of elements of the rows and columns of that matrix.

### Example

public class Main {
public static void main(String[] args) {
int[][] inputMatrix = {{11, 22, 33}, {44, 55, 66}, {77, 88, 99}};

//call the user-defined methods to print the product values
findRowProduct(inputMatrix);
findColumnProduct(inputMatrix);
}

//user-defined method to find the product of row elements
private static void findRowProduct(int[][] mat) {
System.out.println("Product of each row:");
for (int[] r : mat) {
int prod = 1;
for (int value : r) {
prod *= value;
}
System.out.println("The product of the row is: " + prod);
}
}

//user-defined method to find the product of column elements
private static void findColumnProduct(int[][] mat) {
System.out.println("\nProduct of each column:");
for (int a = 0; a < mat[0].length; a++) {
int prod = 1;
for (int b = 0; b < mat.length; b++) {
prod *= mat[b][a];
}
System.out.println("The product of the column " + (a + 1) + " is: " + prod);
}
}
}


### Output

Product of each row:
The product of the row is: 7986
The product of the row is: 159720
The product of the row is: 670824

Product of each column:
The product of the column 1 is: 37268
The product of the column 2 is: 106480
The product of the column 3 is: 215622


In this article, we explored different approaches to find the product of each row and column elements of a matrix by one by using Java programming language.

Updated on: 04-May-2023

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