How to sum numbers that are in columns from a text file in Java?

Question

I am trying to read from a file with multiple lines and then add the numbers in columns. However, I struggle to separate numbers into int variables from same lines so that I could add them eventually.

Basically, I would like to know how to read from a file and sum the columns below:

11 33
22 2
33 1

So that I would get 66 and 36

Answer 1

Assuming the file name is "filename.txt"...

import java.io.BufferedReader;
import java.io.FileReader;

public class SumColumns  
{  
   public static void main(String args[])
   {  
        int firstCol = 0, secondCol = 0;
        BufferedReader reader;
        try {

            reader = new BufferedReader(new FileReader("./filename.txt"));
            
            String line;
            String[] columns;
            
            while ((line = reader.readLine()) != null) {
                columns = line.split(" ");
                firstCol += Integer.parseInt(columns[0]);
                secondCol += Integer.parseInt(columns[1]);
            }
            
        } catch (Exception e) {

        }
        

        System.out.println(firstCol);
        System.out.println(secondCol);
        
   }  
}