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abhilash

Given a matrix, print the sum of the row elements in the matrix.

For example, consider the matrix below.

```
[1, 2, 3]
[4, 5, 6]
[7, 8, 9]
```

The row sum of the matrix above is as follows.

```
6
15
24
```

- The first row in the output, (
`6`

) indicates the sum of the elements of the first row, i.e.,`1`

,`2`

, and`3`

. - The second row in the output, (
`15`

) indicates the sum of the elements of the second row, i.e.,`4`

,`5`

, and`6`

. - The third row in the output, (
`24`

) indicates the sum of the elements of the third row, i.e.,`7`

,`8`

, and`9`

.

- Create an array of size equal to the number of rows. This array is used to store the row sum of every row. Let the array be
`rowSum`

. - Iterate through every row of the matrix and execute the following:
- Initialize a sum variable to zero.
- Loop through all the elements in the row.
- Add every element to the sum variable.

- Add the sum variable to the
`rowSum`

array defined in Step 1 of the algorithm.

- Return the
`rowSum`

array.

- Time complexity - O(N*N)
- Space complexity - O(N)

import java.util.Arrays; public class Main{ private static int[] printRowSum(int[][] matrix){ int numRows = matrix.length; int numCols = matrix[0].length; int[] rowSum = new int[numRows]; for(int i = 0; i < numRows; i++) { int sum = 0; for(int j = 0; j < numCols; j++) sum += matrix[i][j]; rowSum[i] = sum; } return rowSum; } private static void printMatrix(int[][] matrix){ for (int[] row : matrix) System.out.println(Arrays.toString(row)); } public static void main(String[] args){ int matrix[][] = {{1, 2, 3}, {4, 5, 6}, {7, 8 , 9}}; printMatrix(matrix); System.out.println("The row sum of the above matrix is as follows:"); int[] rowSum = printRowSum(matrix); for(int i: rowSum) System.out.println(i); } }

Row Sum of matrix

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