Pari has a friend who loves palindrome numbers. A palindrome number is a number that reads the same forward or backward. For example $12321$, $100001$ and $1$ are palindrome numbers, while $112$ and $1021$ are not.

Pari is trying to love them too, but only very special and gifted people can understand the beauty behind palindrome numbers. Pari loves integers with even length (i.e. the numbers with even number of digits), so she tries to see a lot of big palindrome numbers with even length (like a $2$-digit $11$ or $6$-digit $122221$), so maybe she could see something in them.

Now Pari asks you to write a program that gets a huge integer $*n*$ from the input and tells what is the $*n*$-th even-length positive palindrome number?

Input

The only line of the input contains a single integer $*n*$ ($1 ≤ *n* ≤ 10^{100 000}$).

Output

Print the $*n*$-th even-length palindrome number.

Note

The first $10$ even-length palindrome numbers are $11, 22, 33, ... , 88, 99$ and $1001$.