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 sc = new Scanner(System.in);
 String s = sc.next();
 char[] alp = {'a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z'};
 if(s.length() < 26) {
	 char ad = 0;
	 for(int i = 0;i < 26;i++) {
		 boolean dif = true;
		 for(int j = 0;j < s.length();j++) {
			 if(alp[i] == s.charAt(j)) {
				 dif = false;
				 break;
			 }
			 else dif = true;
			 }if(dif) {
				 ad = alp[i];
				 break;
			 }
			 }
	 System.out.print(s);
	 System.out.println(ad);
		 }
 else if(s.length() == 26) {
	 if(s.equals( "zyxwvutsrqponmlkjihgfedcba"))System.out.println("-1");
	 else {
		 int swap = -1;
		 for(int i = 25;i > 0;i--) {
			 int a = -1;
			 int b = -1;
			 for(int j = 0;j < 26;j++) {
				 if(s.charAt(i) == alp[j]) {
					 a = j;
					 break;
				 }
			 }
			 for(int j = 0;j < 26;j++) {
				 if(s.charAt(i-1) == alp[j]) {
					 b = j;
					 break;
				 }
			 }
			 if(a > b) {
				 swap = i-1;
				 break;
			 }
			 
		 }
		 int min = 25;
		 if(swap == 0) {min = 25;
		 int swapin = -1;
		 for(int j = 0;j < 26;j++) {
			 if(s.charAt(swap) == alp[j]){
				 swapin = j;
			 }
		 }
		 for(int i = swap+1;i < 26;i++) {
			 for(int j = 0;j < 26;j++) {
				 if(s.charAt(i) == alp[j]){
					 if(j > swapin)
					 min = Math.min(min,j);
				 }
			 }
		 }
			 System.out.println(alp[min]);
		 }
		 else {
			 min = 25;
			 int swapin = -1;
			 for(int j = 0;j < 26;j++) {
				 if(s.charAt(swap) == alp[j]){
					 swapin = j;
				 }
			 }
			 for(int i = swap+1;i < 26;i++) {
				 for(int j = 0;j < 26;j++) {
					 if(s.charAt(i) == alp[j]){
						 if(j > swapin)
						 min = Math.min(min,j);
					 }
				 }
			 }
			 System.out.print(s.substring(0,swap));
			 System.out.println(alp[min]);
	 }
	 }
	 
 }
	 }
 }
