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 CPP):

Solution:
#include <bits/stdc++.h>
using namespace std;
const int infi = 1e9;
const long long int infl = 1e18;
const int MOD = 1e9 + 7;
long long int log_2(long long int n) {
  return (n > 1ll) ? 1ll + log_2(n / 2) : 0ll;
}
inline void add(long long int &a, long long int b) {
  a += b;
  if (a >= MOD) a -= MOD;
}
inline void sub(long long int &a, long long int b) {
  a -= b;
  if (a < 0) a += MOD;
}
inline string IntToString(long long int a) {
  char x[100];
  sprintf(x, "%lld", a);
  string s = x;
  return s;
}
inline long long int StringToInt(string a) {
  char x[100];
  long long int res;
  strcpy(x, a.c_str());
  sscanf(x, "%lld", &res);
  return res;
}
inline string GetString(void) {
  char x[1000005];
  scanf("%s", x);
  string s = x;
  return s;
}
inline string uppercase(string s) {
  int n = (int)s.size();
  for (int(i) = (0); (i) < (n); ++(i))
    if (s[i] >= 'a' && s[i] <= 'z') s[i] = s[i] - 'a' + 'A';
  return s;
}
inline string lowercase(string s) {
  int n = (int)s.size();
  for (int(i) = (0); (i) < (n); ++(i))
    if (s[i] >= 'A' && s[i] <= 'Z') s[i] = s[i] - 'A' + 'a';
  return s;
}
inline void OPEN(string s) {
  freopen((s + ".in").c_str(), "r", stdin);
  freopen((s + ".out").c_str(), "w", stdout);
}
void showarr(long long int arr[], long long int n) {
  int i;
  for (i = 0; i < n; i++) {
    cout << arr[i] << " ";
  }
  cout << endl;
}
void showvec(vector<long long int> v) {
  int i;
  for (i = 0; i < v.size(); i++) {
    cout << v[i] << " ";
  }
  cout << endl;
}
int isPalindrome(string str) {
  int l = 0;
  int h = str.length() - 1;
  while (h > l) {
    if (str[l++] != str[h--]) {
      return 0;
    }
  }
  return 1;
}
void showvecpair(vector<pair<long long int, long long int> > v) {
  for (int i = 0; i < (int)v.size(); i++) {
    cout << v[i].first << " " << v[i].second << endl;
  }
}
bool sortbysec(const pair<long long int, long long int> &a,
               const pair<long long int, long long int> &b) {
  return (a.second < b.second);
}
void bin(unsigned n) {
  unsigned i;
  for (i = 1 << 31; i > 0; i = i / 2) (n & i) ? printf("1") : printf("0");
}
long long int cntset(long long int n) {
  bitset<64> b1(n);
  return b1.count();
}
long long int setBitNumber(long long int n) {
  if (n == 0) return 0;
  long long int msb = 0;
  n = n / 2;
  while (n != 0) {
    n = n / 2;
    msb++;
  }
  return (msb);
}
long long int p[100005];
void seive() {
  long long int i, j;
  for (i = 0; i < 100005; i++) p[i] = i;
  for (i = 2; i <= sqrt(100005); i++) {
    if (p[i] != i) continue;
    for (j = i * i; j < 100005; j += i) {
      if (p[j] == j) p[j] = i;
    }
  }
  return;
}
long long int power(long long int n, long long int x) {
  long long int j = n, prod = 1;
  while (x) {
    if (x % 2) {
      prod = ((prod % MOD) * (j % MOD)) % MOD;
    }
    j = (j * j) % MOD;
    x = x / 2;
  }
  return prod;
}
long long int fact(long long int n) {
  long long int i, prod = 1;
  for (i = 1; i <= n; i++) {
    prod = (prod * i) % MOD;
  }
  return prod;
}
vector<int> prefix_function(string s) {
  int n = (int)s.length();
  vector<int> pi(n);
  for (int i = 1; i < n; i++) {
    int j = pi[i - 1];
    while (j > 0 && s[i] != s[j]) j = pi[j - 1];
    if (s[i] == s[j]) j++;
    pi[i] = j;
  }
  return pi;
}
void solve() {
  long long int m, n, l, a, b, i, c, j, Max = INT_MIN, Min = INT_MAX, ctr = 0,
                                        cnt = 0, x, y, prod = 1, low, high,
                                        Max1, Max2;
  string s;
  cin >> s;
  cout << s;
  reverse((s).begin(), (s).end());
  cout << s << endl;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int i, T;
  T = 1;
  for (i = 1; i <= T; i++) {
    solve();
  }
  return 0;
}