#include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i=0;i<(n);i++)
int main(){
  string S;
  cin>>S;
  int A[26]={0};
  if(S=="zyxwvutsrqponmlkjihgfedcba") cout<<-1<<endl;
  else if(S.size()==26){
    rep(i,25){
      if(S[24-i]<S[25-i]){
        rep(j,25){
          if(S[24-i]<S[25-j]){
            S+=S[25-j];
            break;
          }
        }
        S.erase(24-i,i+2);
        cout<<S<<endl;
        break;
      }
    }
  }else{
    rep(i,S.size()) A[S[i]-'a']++;
    rep(i,26){
      if(!A[i]){
        cout<<S<<char('a'+i)<<endl;
        break;
      }
    }
  }
}
### Prompt

Please create a solution in CPP to the following problem:

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

### Response

```cpp
#include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i=0;i<(n);i++)
int main(){
  string S;
  cin>>S;
  int A[26]={0};
  if(S=="zyxwvutsrqponmlkjihgfedcba") cout<<-1<<endl;
  else if(S.size()==26){
    rep(i,25){
      if(S[24-i]<S[25-i]){
        rep(j,25){
          if(S[24-i]<S[25-j]){
            S+=S[25-j];
            break;
          }
        }
        S.erase(24-i,i+2);
        cout<<S<<endl;
        break;
      }
    }
  }else{
    rep(i,S.size()) A[S[i]-'a']++;
    rep(i,26){
      if(!A[i]){
        cout<<S<<char('a'+i)<<endl;
        break;
      }
    }
  }
}
```