Project Euler - Problem 13

euler.java

package euler;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.math.BigInteger;

public class LongSum {
	public static void main(String[] args) throws Throwable {
		
		BufferedReader br = new BufferedReader(new FileReader(new File("numbers.txt")));
		
		String line;
		
		BigInteger sum = BigInteger.ZERO;
		
		while((line = br.readLine()) != null) {
			sum = sum.add(new BigInteger(line));
		}
		br.close();
		
		System.out.println(sum.toString().substring(0,10));
		
	}

}