Manipulating a 2D array from a file in Java

Problem:

Using a scanner, you should read a 2D array from a file called "numbers.txt". The first line in the file will have two integers which are the number of rows and columns respectively. After reading the two integers, you should create a 2D array in your code that has the same number of rows and columns read. Then, you continue reading the 2D array from the file.

After reading the 2D array, you need to add the value of the previous column on the current row to the current column on the current row. (Hint: ADM] += A[i][j-1])

Finally, save your array to a file called "newNumbers.txt" using a formatter.

Output:

43
123
234
456
678

136
259
4915
61321

Solution:

import java.io.File;
import java.util.Formatter;
import java.util.Scanner;

public class ProblemC {

 public static void main(String args[]) {
  try {
   Scanner scan = new Scanner(new File("numbers.txt"));
   Formatter formatter = new Formatter(new File("newNumbers.txt"));
   
   int rows = scan.nextInt();
   int cols = scan.nextInt();
   
   int A[][] = new int[rows][cols];
   
   for (int i = 0; i < rows; i++)
    for (int j = 0; j < cols; j++)
     A[i][j] = scan.nextInt();
   
   for (int i = 0; i < rows; i++)
    for (int j = 1; j < cols; j++)
     A[i][j] += A[i][j-1];
   
   for (int i = 0; i < rows; i++) {
    for (int j = 0; j < cols; j++)
     formatter.format("%d ", A[i][j], true);
    
    formatter.format("\n", "", true);
   }
   
   scan.close();
   formatter.close();
   
  } catch (Exception e) {
   System.err.println("File error");
  }
 }
}