Problem: You are given a string s consisting of |s| small english letters.

In one move you can replace any character of this string to the next character in alphabetical order (a will be replaced with b, s will be replaced with t, etc.). You cannot replace letter z with any other letter.

Your target is to make some number of moves (not necessary minimal) to get string abcdefghijklmnopqrstuvwxyz (english alphabet) as a subsequence. Subsequence of the string is the string that is obtained by deleting characters at some positions. You need to print the string that will be obtained from the given string and will be contain english alphabet as a subsequence or say that it is impossible.

Input

The only one line of the input consisting of the string s consisting of |s| (1 ≤ |s| ≤ 105) small english letters.

Output

If you can get a string that can be obtained from the given string and will contain english alphabet as a subsequence, print it. Otherwise print «-1» (without quotes).

Examples

Input

aacceeggiikkmmooqqssuuwwyy


Output

abcdefghijklmnopqrstuvwxyz


Input

thereisnoanswer


Output

-1

Solution (in JAVA):

Solution:
import java.util.*;
import java.io.*;
 
public class MainC
{

    static int mod = (int) (1e9+7);
    static InputReader in;
    static PrintWriter out;
    
    public static void main(String[] args)
    {
        in = new InputReader(System.in);
        out = new PrintWriter(System.out);            
        
        String s = in.readString();
        int[] cnt = new int[26];
        StringBuilder str = new StringBuilder();
        int j = 0;
        for(int i = 0; i < s.length(); i++){
            int x = (int)(s.charAt(i) - 'a');
            if(j == 26){
                str.append((char)(x + 'a'));
                continue;
            }
            if(x <= j){
                str.append((char)(j + 'a'));
                j++;
            }
            else{
                str.append((char)(x + 'a'));
            }
        }
        
        out.println(j == 26 ? str.toString() : -1);
        out.close();
    }
    
    
    static class Pair implements Comparable<Pair>
    {

        int x,y,z;
        
        Pair (int x,int y, int z)
        {
            if(x > y){
                if(y > z){
                    this.x = z;
                    this.y = y;
                    this.z = x;
                }
                else{
                    if(x > z){
                        this.z = x;
                        this.y = z;
                        this.x = y;
                    }
                    else{
                        this.z = z;
                        this.y = x;
                        this.x = y;
                    }
                }
            }
            else{
                if(y < z){
                    this.x = x;
                    this.y = y;
                    this.z = z;
                }
                else{
                    if(x > z){
                        this.z = y;
                        this.y = x;
                        this.x = z;
                    }
                    else{
                        this.z = y;
                        this.y = z;
                        this.x = x;
                    }
                }
            }
	}
        
	public int compareTo(Pair o)
        {
            if(this.z == o.z){
                
            }
                
            return -Integer.compare(this.z,o.z);
		//return 0;
	}

        public boolean equals(Object o)
        {
            if (o instanceof Pair)
            {
                Pair p = (Pair)o;
                return p.x == x && p.y==y;
            }
            return false;
        }

        @Override
        public String toString()
        {
            return x + " "+ y + " " + z;
        }
        
        public int hashCode()
        {
            return new Long(x).hashCode() * 31 + new Long(y).hashCode();
        }
    
    }

 
    static long add(long a, long b) {
        long x = (a + b);
        while (x >= mod) {
            x -= mod;
        }
        return x;
    }

    static long sub(long a, long b) {
        long x = (a - b);
        while (x < 0) {
            x += mod;
        }
        return x;
    }

    static String rev(String s) {
        StringBuilder sb = new StringBuilder(s);
        sb.reverse();
        return sb.toString();
    }
    
    static long gcd(long x,long y)
    {
        x = Math.abs(x);
        y = Math.abs(y);
        if(y==0)
                return x;
        else
                return gcd(y,x%y);
    }
 
    static int gcd(int x,int y)
    {
        x = Math.abs(x);
        y = Math.abs(y);
        if(y==0)
                return x;
        else 
                return gcd(y,x%y);
    }
 
    static long pow(long n,long p,long m)
    {
         long  result = 1;
          if(p==0){
            return 1;
          }
          
        while(p!=0)
        {
            if(p%2==1)
                result *= n;
            if(result >= m)
               result %= m;
            p >>=1;
            n*=n;
            if(n >= m)
                n%=m;
        }
        
        return result;
    }
 
    static long pow(long n,long p)
    {
        long  result = 1;
          if(p==0)
            return 1;
 
        while(p!=0)
        {
            if(p%2==1)
                result *= n;	    
            p >>=1;
            n*=n;	    
        }
        return result;
    }
 
    static void debug(Object... o)
    {
            System.out.println(Arrays.deepToString(o));
    }
 
    static class InputReader
    {
 
        private final InputStream stream;
        private final byte[] buf = new byte[8192];
        private int curChar, snumChars;
        private SpaceCharFilter filter;
 
        public InputReader(InputStream stream)
        {
                this.stream = stream;
        }
 
        public int snext()
        {
                if (snumChars == -1)
                        throw new InputMismatchException();
                if (curChar >= snumChars)
                {
                        curChar = 0;
                        try
                        {
                                snumChars = stream.read(buf);
                        } catch (IOException e)
                        {
                                throw new InputMismatchException();
                        }
                        if (snumChars <= 0)
                                return -1;
                }
                return buf[curChar++];
        }
 
        public int nextInt()
        {
                int c = snext();
                while (isSpaceChar(c))
                {
                        c = snext();
                }
                int sgn = 1;
                if (c == '-')
                {
                        sgn = -1;
                        c = snext();
                }
                int res = 0;
                do
                {
                        if (c < '0' || c > '9')
                                throw new InputMismatchException();
                        res *= 10;
                        res += c - '0';
                        c = snext();
                } while (!isSpaceChar(c));
                return res * sgn;
        }
 
        public long nextLong()
        {
                int c = snext();
                while (isSpaceChar(c))
                {
                        c = snext();
                }
                int sgn = 1;
                if (c == '-')
                {
                        sgn = -1;
                        c = snext();
                }
                long res = 0;
                do
                {
                        if (c < '0' || c > '9')
                                throw new InputMismatchException();
                        res *= 10;
                        res += c - '0';
                        c = snext();
                } while (!isSpaceChar(c));
                return res * sgn;
        }
 
        public int[] nextIntArray(int n)
        {
                int a[] = new int[n];
                for (int i = 0; i < n; i++)
                {
                        a[i] = nextInt();
                }
                return a;
        }
 
        public long[] nextLongArray(int n)
        {
                long a[] = new long[n];
                for (int i = 0; i < n; i++)
                {
                        a[i] = nextLong();
                }
                return a;
        }
 
        public String readString()
        {
                int c = snext();
                while (isSpaceChar(c))
                {
                        c = snext();
                }
                StringBuilder res = new StringBuilder();
                do
                {
                        res.appendCodePoint(c);
                        c = snext();
                } while (!isSpaceChar(c));
                return res.toString();
        }
 
        public String nextLine()
        {
                int c = snext();
                while (isSpaceChar(c))
                        c = snext();
                StringBuilder res = new StringBuilder();
                do
                {
                        res.appendCodePoint(c);
                        c = snext();
                } while (!isEndOfLine(c));
                return res.toString();
        }
 
        public boolean isSpaceChar(int c)
        {
                if (filter != null)
                        return filter.isSpaceChar(c);
                return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
        }
 
        private boolean isEndOfLine(int c)
        {
                return c == '\n' || c == '\r' || c == -1;
        }
 
        public interface SpaceCharFilter
        {
                public boolean isSpaceChar(int ch);
        }
 
    }
}