Problem: 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 ≤ 10100 000).

Output

Print the n-th even-length palindrome number.

Examples

Input

1


Output

11


Input

10


Output

1001

Note

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

Solution (in PYTHON):

Solution:
__author__ = 'Devesh Bajpai'

'''
https://codeforces.com/problemset/problem/688/B

Solution: If we observe the first few palindromes of even length, for the first 9 palindromes,
we get 11 to 99. After that, we go to 1001 and then put these 11 to 99 between two 1s. This results in
palindromes 1111, 1221, 1331 to 1991. If we observe the behavior, we see that this progression is like
the natural numbers. So the 5th such palindrome is 55, 9th is 99, 10th is 1001, 15th is 1551. Hence the
palindrome can be obtained by suffixing n with its reverse. 

Since we want to reverse n, it makes sense to keep the input in string itself. 
'''


def solve(n):

    return n + ''.join(reversed(n))


if __name__ == "__main__":

    n = raw_input()
    print solve(n)