Problem Description

Given two positive integers $ A $ and $ B $, concatenate the decimal notation of $ A $ to the right of the decimal notation of $ B $ (without leading zeros) to obtain an integer. Output the result of multiplying this integer by 2.

Input Format

The input is given from the standard input in the following format:

$ A $ $ B $

• The first line contains two integers $ A $ and $ B $ ($ 1 $ $ ≦ $ $ A, $ $ B $ $ ≦ $ $ 999 $) separated by a space.

Output Format

Output the specified value to the standard output.

Do not forget the newline at the end.

Sample Input and Output

Sample Input #1

1 23

Sample Output #1

246

Sample Input #2

999 999

Sample Output #2

1999998

Notes/Hints

Sample Explanation 1

$123\ ×\ 2\ =\ 246$

见题面 Input 部分

见题面 Output 部分