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 JAVA):

Solution:
import java.util.*;
import javax.naming.directory.InvalidAttributesException;
import java.io.InputStreamReader;
import java.io.Writer;
import java.io.BufferedReader;
import java.io.IOException;
import java.lang.Math;
import java.io.BufferedWriter;
import java.io.OutputStreamWriter;
import java.io.OutputStream;
import java.io.PrintWriter;

public class one {

  static boolean isPalindrome(String word) {
    word = word.toLowerCase();
    int start = 0;
    int end = word.length() - 1;
    boolean flag = true;
    while (start <= end) {
      if (word.charAt(start) != word.charAt(end)) {
        flag = false;
        break;
      } else
        start++;
      end--;
    }
    return flag;
  }

  static boolean isTriangle(int a,int b,int c)
  {
    boolean flag=false;
    if(a+b > c && b+c > a && c+a > b)flag=true;
    return flag;
  }

  static boolean isVowel(char x) {
    if (x == 'a' || x == 'e' || x == 'i' || x == 'o' || x == 'u' || x == 'A' || x == 'E' || x == 'I' || x == 'O'
        || x == 'U')
      return true;
    else
      return false;
  }

  static boolean isPrime(int n) {

    if (n <= 1)
      return false;
    if (n <= 3)
      return true;

    if (n % 2 == 0 || n % 3 == 0)
      return false;

    for (int i = 5; i * i <= n; i = i + 6)
      if (n % i == 0 || n % (i + 2) == 0)
        return false;

    return true;
  }

  static int nCr(int n, int r) {
    return fact(n) / (fact(r) * fact(n - r));
  }

  // Returns factorial of n
  static int fact(int n) {
    int res = 1;
    for (int i = 2; i <= n; i++)
      res = res * i;
    return res;
  }

  static boolean isPerfectSquare(double x) {
    double sr = Math.sqrt(x);
    return ((sr - Math.floor(sr)) == 0);
  }

  static int gcd(int a, int b) {
    if (b == 0)
      return a;
    return gcd(b, a % b);
  }

  static long gcd(long a, long b) {
    if (b == 0)
      return a;
    return gcd(b, a % b);
  }

  static long lcm(long a, long b) {
    return (a * b) / gcd(a, b);
  }

  static class FastReader {
    BufferedReader br;
    StringTokenizer st;

    public FastReader() {
      br = new BufferedReader(new InputStreamReader(System.in));
    }

    String next() {
      while (st == null || !st.hasMoreElements()) {
        try {
          st = new StringTokenizer(br.readLine());
        } catch (IOException e) {
          e.printStackTrace();
        }
      }
      return st.nextToken();
    }

    int nextInt() {
      return Integer.parseInt(next());
    }

    long nextLong() {
      return Long.parseLong(next());
    }

    double nextDouble() {
      return Double.parseDouble(next());
    }

    String nextLine() throws IOException, InvalidAttributesException {
      String str = "";
      str = br.readLine();
      return str;
    }

    public int[] nextIntArray(int n) {
      int[] array = new int[n];
      for (int i = 0; i < n; ++i)
        array[i] = nextInt();
      return array;
    }

    public long[] nextLongArray(int n) {
      long[] array = new long[n];
      for (int i = 0; i < n; ++i)
        array[i] = nextLong();
      return array;
    }

    public ArrayList<Integer> nextIntArrayList(int n) {
      ArrayList<Integer> ar = new ArrayList<>();
      for (int i = 0; i < n; i++)
        ar.add(nextInt());
      return ar;
    }

    public ArrayList<Long> nextLongArrayList(int n) {
      ArrayList<Long> ar = new ArrayList<>();
      for (int i = 0; i < n; i++)
        ar.add(nextLong());
      return ar;
    }

    public int[][] nextIntMatrix(int n, int m) {
      int[][] matrix = new int[n][m];
      for (int i = 0; i < n; ++i)
        for (int j = 0; j < m; ++j)
          matrix[i][j] = nextInt();
      return matrix;
    }

    public long[][] nextLongMatrix(int n, int m) {
      long[][] matrix = new long[n][m];
      for (int i = 0; i < n; ++i)
        for (int j = 0; j < m; ++j)
          matrix[i][j] = nextLong();
      return matrix;
    }

    public char[][] nextCharMatrix(int n, int m) {
      char[][] matrix = new char[n][m];
      for (int i = 0; i < n; ++i)
        matrix[i] = next().toCharArray();
      return matrix;
    }

  }

  static class OutputWriter {
    private final PrintWriter writer;

    public OutputWriter(OutputStream outputStream) {
      writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream)));
    }

    public OutputWriter(Writer writer) {
      this.writer = new PrintWriter(writer);
    }

    public void print(Object... objects) {
      for (int i = 0; i < objects.length; i++) {
        if (i != 0) {
          writer.print(' ');
        }
        writer.print(objects[i]);
      }
    }

    public void print(int[] array) {
      for (int i = 0; i < array.length; i++) {
        if (i != 0) {
          writer.print(' ');
        }
        writer.print(array[i]);
      }
    }

    public void print(double[] array) {
      for (int i = 0; i < array.length; i++) {
        if (i != 0) {
          writer.print(' ');
        }
        writer.print(array[i]);
      }
    }

    public void print(long[] array) {
      for (int i = 0; i < array.length; i++) {
        if (i != 0) {
          writer.print(' ');
        }
        writer.print(array[i]);
      }
    }

    public void print(char[] array) {
      for (int i = 0; i < array.length; i++) {
        if (i != 0) {
          writer.print(' ');
        }
        writer.print(array[i]);
      }
    }

    public void print(String[] array) {
      for (int i = 0; i < array.length; i++) {
        if (i != 0) {
          writer.print(' ');
        }
        writer.print(array[i]);
      }
    }

    public void print(int[][] matrix) {
      for (int i = 0; i < matrix.length; ++i) {
        println(matrix[i]);
      }
    }

    public void print(double[][] matrix) {
      for (int i = 0; i < matrix.length; ++i) {
        println(matrix[i]);
      }
    }

    public void print(long[][] matrix) {
      for (int i = 0; i < matrix.length; ++i) {
        println(matrix[i]);
      }
    }

    public void print(char[][] matrix) {
      for (int i = 0; i < matrix.length; ++i) {
        println(matrix[i]);
      }
    }

    public void print(String[][] matrix) {
      for (int i = 0; i < matrix.length; ++i) {
        println(matrix[i]);
      }
    }

    public void println(int[] array) {
      print(array);
      writer.println();
    }

    public void println(double[] array) {
      print(array);
      writer.println();
    }

    public void println(long[] array) {
      print(array);
      writer.println();
    }

    public void println(String[] array) {
      print(array);
      writer.println();
    }

    public void println() {
      writer.println();
    }

    public void println(Object... objects) {
      print(objects);
      writer.println();
    }

    public void print(char i) {
      writer.print(i);
    }

    public void println(char i) {
      writer.println(i);
    }

    public void println(char[] array) {
      writer.println(array);
    }

    public void printf(String format, Object... objects) {
      writer.printf(format, objects);
    }

    public void close() {
      writer.close();
    }

    public void flush() {
      writer.flush();
    }

    public void print(long i) {
      writer.print(i);
    }

    public void println(long i) {
      writer.println(i);
    }

    public void print(int i) {
      writer.print(i);
    }

    public void println(int i) {
      writer.println(i);
    }

    public void separateLines(int[] array) {
      for (int i : array) {
        println(i);
      }
    }
  }

 
  public static void main(String[] args) {
    FastReader sc = new FastReader();
    OutputStream outputStream = System.out;
    OutputWriter out = new OutputWriter(outputStream);

    // int t = sc.nextInt();

    // while (t-- > 0) {

   // Long N = sc.nextLong();
    //String s1 = String.valueOf(N);
String s1 = sc.next();
    int n = s1.length();
    
    char[] arr = new char [2*n];
    for(int i=0;i<n;i++)
    {
      arr[i]=s1.charAt(i);
    }
   
    int k=0;
    for(int i=2*n-1;i>=n;i--)
    {
      arr[i]=s1.charAt(k);
      k++;
    }
  for(int i=0;i<2*n;i++)
  {
    out.print(arr[i]);
  }
  out.println();


    


    // }
    out.flush();
    out.close();

  }
}