Gotou just received a dictionary. However, he doesn't recognize the language used in the dictionary. He did some analysis on the dictionary and realizes that the dictionary contains all possible diverse words in lexicographical order.

A word is called diverse if and only if it is a nonempty string of English lowercase letters and all letters in the word are distinct. For example, `atcoder`, `zscoder` and `agc` are diverse words while `gotou` and `connect` aren't diverse words.

Given a diverse word S, determine the next word that appears after S in the dictionary, i.e. the lexicographically smallest diverse word that is lexicographically larger than S, or determine that it doesn't exist.

Let X = x_{1}x_{2}...x_{n} and Y = y_{1}y_{2}...y_{m} be two distinct strings. X is lexicographically larger than Y if and only if Y is a prefix of X or x_{j} > y_{j} where j is the smallest integer such that x_{j} \neq y_{j}.

Constraints

* 1 \leq |S| \leq 26
* S is a diverse word.

Input

Input is given from Standard Input in the following format:


S


Output

Print the next word that appears after S in the dictionary, or `-1` if it doesn't exist.

Examples

Input

atcoder


Output

atcoderb


Input

abc


Output

abcd


Input

zyxwvutsrqponmlkjihgfedcba


Output

-1


Input

abcdefghijklmnopqrstuvwzyx


Output

abcdefghijklmnopqrstuvx
import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner cin = new Scanner(System.in);
        String w = cin.next();
        String allChars = "abcdefghijklmnopqrstuvwxyz";
        if (w.length() < 26) {
            int firstUnused = allChars
                    .chars()
                    .filter((int n) -> (w.indexOf(n) == -1))
                    .findFirst()
                    .orElse(-1);
            System.out.println(w + (char)firstUnused);
        } else {
            String rev = (new StringBuffer(allChars)).reverse().toString();
            if (rev.equals(w)) {
                System.out.println("-1");
                return;
            }

            StringBuffer buf = new StringBuffer(w);
            for (int i = w.length() - 1; i >= 0; i--) {
                int c = buf.charAt(i);
                buf.setLength(buf.length() - 1);
                if (c != (int)'z') {
                    for (int c2 = c + 1; c2 <= (int)'z'; c2++) {
                        if (buf.toString().indexOf(c2) == -1) {
                            System.out.println(buf.toString() + (char)(c2));
                            return;
                        }
                    }
                }
            }
        }
    }
}
