import java.io.File;

import java.io.FileNotFoundException;

import java.io.PrintWriter;

import java.util.Scanner;

public class TwiceData {

public static void main(String[] args) {

Scanner infile;

PrintWriter pw;

try {

infile = new Scanner(new File("nums.txt"));

pw = new PrintWriter("twice_nums.txt");

int inputNum;

while(infile.hasNext()) {

inputNum = infile.nextInt();

inputNum *= 2; //multiply by 2

pw.println(inputNum);

}//end while

infile.close();

pw.close();

}

catch(FileNotFoundException ex) {

System.out.println(ex.getMessage());

}//end try-catch

}//end main

}