#include <bits/stdc++.h>
using namespace std;

#define loop(i,b,e) for(auto i=b;i<=e;i++)
#define reloop(i,e,b) for(auto i=e;i>=b;i--)
#define all(x) x.begin(),x.end()
#define ll long long
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define pf printf
#define sf scanf

string s,alph="abcdefghijklmnopqrstuvwxyz";
int j;

int main() {
   cin >> s;
   if(s.length() < 26) {
      pf("-1");
      return 0;
   }
   loop(i,0,s.length()-1)
      if(s[i] <= alph[j]) s[i] = alph[j],j++;
   if(j < 26) pf("-1");
   else cout << s;
}