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 PYTHON3):

Solution:
from math import gcd
from functools import reduce
from itertools import accumulate
from typing import List
import bisect
import random
from itertools import permutations, combinations
from collections import Counter


def listAll(func, nums: list) -> bool:
    for x in nums:
        if not func(x):
            return False
    return True


def transformStrings(func) -> list:
    return list(map(func, readStrings()))


def getOrNone(iterable, index):
    if 0 <= index < len(iterable):
        return iterable[index]
    return None


def getOrDefault(iterable, index, default):
    if 0 <= index < len(iterable):
        return iterable[index]
    return default


def digitSum(num: int) -> int:
    numString = str(num)
    value = 0
    for x in numString:
        value += int(x)
    return value


def runningReduce(func, nums: list) -> list:
    values = nums.copy()
    for x in range(1, len(nums)):
        values[x] = func(values[x - 1], nums[x])
    return values


def lcm(a, b) -> int:
    return abs(a * b) // gcd(a, b)


def printList(nums: list, end="\n"):
    nums = list(map(lambda x: str(x), nums))
    print(" ".join(nums), end=end)


def readStrings() -> List[str]:
    return input().split(" ")


def readInt() -> int:
    return int(input())


def readInts() -> List[int]:
    return list(map(lambda x: int(x), readStrings()))


def readOtherNumericTypes(func) -> list:
    return list(map(func, readStrings()))


def isEven(num: int) -> bool:
    return num % 2 == 0


def isPositive(num: int) -> bool:
    return num > 0


def isPositiveOrZero(num: int) -> bool:
    return isPositive(num) or num == 0


def digits(num: int) -> int:
    return len(str(num))


def firstDigit(num: int) -> int:
    return int(str(num)[0])


num = input()
print(num + num[::-1])