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.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.math.BigInteger;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.Stack;
import java.util.StringTokenizer;

public class Solution implements Runnable
{
    private void solve() throws IOException
    {
    	
    	//int n = nextInt();
    	String n = nextToken();
    	
    	StringBuilder rsb = new StringBuilder(n).reverse();
    	StringBuilder sb = new StringBuilder(n);
    	sb.append(rsb);
    	
    	writer.print(sb.toString());	
    	
    }
        
    private boolean isPowerOfTwo(long x) {
        return (x != 0) && ((x & (x - 1)) == 0);
    }
    
    private int exponentOfTwo(long n) {
    	return (int)( Math.floor(Math.log(n) / Math.log(2)));

    }

    private Long sumDiagLR (Long[][] array) {
        long sum = 0;
        int i = 0, j = 0;

        while (i < array.length && j < array.length) {
            sum += array[i][j];
            i++;
            j++;
        }

        return sum;
    }

    private Long sumDiagRL (Long[][] array) {
       long sum = 0;
       int i = array.length-1, j = 0;

       while (i >=0 && j < array.length) {
           sum += array[i][j];
           i--;
           j++;
       }

       return sum;
   }


    private BigInteger factorial( String n )
    {
        BigInteger k = new BigInteger( n );
        BigInteger ans = BigInteger.ONE;

        while ( k.compareTo( BigInteger.ONE ) > 0 )
        {
            ans = ans.multiply( k );
            k = k.subtract( BigInteger.ONE );
        }

        return ans;
    }

    private long combinations( int n, int r )
    {
        return ( factorial( String.valueOf( n ) ).divide( ( new BigInteger( String.valueOf( r ) ).multiply( factorial( String.valueOf( n - r ) ) ) ) ) ).longValue();
    }


    private String binaryXOR( String s1, String s2 )
    {
        BigInteger a = new BigInteger( s1, 2 );
        BigInteger b = new BigInteger( s2, 2 );

        return a.xor( b ).toString( 2 );

    }


    private static void findDP( Node node )
    {
        for ( Node child : node.children )
        {
            if ( child.value > node.value )
            {
                child.dp = Math.max( child.dp, node.dp + 1 );
                //findDP( child );
            }
        }
    }

    private static class Obj implements Comparable<Obj>
    {
        String name;
        int value;

        public Obj( int value )
        {
            this.value = value;
        }

        public Obj( String name, int value )
        {
            this.name = name;
            this.value = value;
        }

        @Override
        public int compareTo( Obj o )
        {
            return o.value - this.value;
        }
    }


    private static class Edge
    {
        PNode src;
        PNode des;
        long cost;

        public Edge (PNode src, PNode des, long cost) {
            this.src = src;
            this.des = des;
            this.cost = cost;
        }
    }

    private static class PNode
    {
        List<Edge> edges;
        long value;
        boolean isTrue;

        public PNode() {
            this.edges = new ArrayList<>(  );
            this.isTrue = false;
        }

        public PNode(long value ) {
           this.edges = new ArrayList<>(  );
           this.isTrue = false;
            this.value = value;
       }
    }

    private static class Node
    {
        long value;
        long dp;
        List<Node> children;
        Node parent;

        public  Node(){};

        public Node( int value )
        {
            this.value = value;
            dp = 1;
            children = new ArrayList<Node>();
        }
    }

    private static boolean isInt( String s )
    {
        if ( s.length() < 1 )
            return false;
        else
        {
            for ( char c : s.toCharArray() )
            {
                if ( c < '0' || c > '9' )
                {
                    return false;
                }
            }
        }

        return true;
    }

    private static Map<String, Integer> findSubString( String s, int k )
    {
        Map<String, Integer> map = new HashMap<>();
        for ( int i = 0; i < s.length() - ( k - 1 ); i++ )
        {
            String str = new String( s.substring( i, i + k ) );
            if ( map.containsKey( str ) )
            {
                map.put( str, map.get( str ) + 1 );
            }
            else
            {
                map.put( str, 1 );

            }
        }

        return map;
    }


    //mergesort

    public static Comparable[] mergeSort( Comparable[] list )
    {
        if ( list.length <= 1 )
        {
            return list;
        }

        Comparable[] left = new Comparable[ list.length / 2 ];
        Comparable[] right = new Comparable[ list.length - left.length ];
        System.arraycopy( list, 0, left, 0, left.length );
        System.arraycopy( list, left.length, right, 0, right.length );

        mergeSort( left );
        mergeSort( right );

        merge( left, right, list );
        return list;
    }

    private static void merge( Comparable[] left, Comparable[] right, Comparable[] result )
    {
        int leftIdx = 0;
        int rightIdx = 0;
        int index = 0;

        while ( leftIdx < left.length && rightIdx < right.length )
        {
            if ( left[ leftIdx ].compareTo( right[ rightIdx ] ) < 0 )
            {
                result[ index++ ] = left[ leftIdx ];
                leftIdx++;
            }
            else
            {
                result[ index++ ] = right[ rightIdx ];
                rightIdx++;
            }
        }

        System.arraycopy( left, leftIdx, result, index, left.length - leftIdx );
        System.arraycopy( right, rightIdx, result, index, right.length - rightIdx );
    }

    public static List<Obj> mergeSort( List<Obj> list )
    {
        if ( list.size() <= 1 )
        {
            return list;
        }

        List<Obj> left = new ArrayList( list.subList( 0, list.size() / 2 ) );
        List<Obj> right = new ArrayList( list.subList( left.size(), list.size() ) );

        left = mergeSort( left );
        right = mergeSort( right );

        list = merge( left, right );

        return list;
    }

    private static List<Obj> merge( List<Obj> left, List<Obj> right )
    {
        int leftCounter = 0, rightCounter = 0;
        List<Obj> result = new ArrayList<>();

        while ( leftCounter < left.size() && rightCounter < right.size() )
        {
            Obj leftItem = left.get( leftCounter );
            Obj rightItem = right.get( rightCounter );

            if ( leftItem.compareTo( rightItem ) < 0 )
            {
                result.add( leftItem );
                leftCounter++;
            }
            else
            {
                result.add( rightItem );
                rightCounter++;
            }
        }

        if ( leftCounter >= left.size() )
            result.addAll( right.subList( rightCounter, right.size() ) );
        else if ( rightCounter >= right.size() )
            result.addAll( left.subList( leftCounter, left.size() ) );

        return result;
    }

    public static void main( String[] args )
    {
        new Solution().run();
    }

    BufferedReader reader;
    StringTokenizer tokenizer;
    PrintWriter writer;

    public void run()
    {
        try
        {
            reader = new BufferedReader( new InputStreamReader( System.in ) );
            tokenizer = null;
            writer = new PrintWriter( System.out );
            solve();
            reader.close();
            writer.close();
        }
        catch ( Exception e )
        {
            e.printStackTrace();
            System.exit( 1 );
        }
    }

    int nextInt() throws IOException
    {
        return Integer.parseInt( nextToken() );
    }

    long nextLong() throws IOException
    {
        return Long.parseLong( nextToken() );
    }

    double nextDouble() throws IOException
    {
        return Double.parseDouble( nextToken() );
    }

    String nextToken() throws IOException
    {
        while ( tokenizer == null || !tokenizer.hasMoreTokens() )
        {
            tokenizer = new StringTokenizer( reader.readLine() );
        }
        return tokenizer.nextToken();
    }

    // Arrays.sort(array, Comparator.comparing((int[] arr) -> arr[1]));
}