CH1 Super Hard Sum

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.IOException;
import java.math.BigInteger;
import java.util.StringTokenizer;

/*
 * Tuenti Contest
 * Challenge 1 - Super Hard Sum
 * Author: Pedro Antonio Pardal Jimena
 * Email: pardal@alu.uma.es
 */

public class HardSum
{
    private static String sumaLinea( String linea )
    {
        BigInteger sum = BigInteger.ZERO;
        StringTokenizer st = new StringTokenizer( linea, " +" );

        while ( st.hasMoreTokens() )
        {
            BigInteger next;

            try
            {
                next = new BigInteger( st.nextToken() );
            }
            catch ( NumberFormatException e )
            {
                next = BigInteger.ZERO;
            }

            sum = sum.add( next );
        }

        return sum.toString();
    }

    public static void main( String[] args ) throws IOException
    {
        BufferedReader reader = new BufferedReader( new InputStreamReader( System.in ) );

        while ( reader.ready() )
        {
            String linea = reader.readLine();

            System.out.println( sumaLinea( linea ) );
        }
    }
}