#include <bits/stdc++.h>
using namespace std;
void IO() {
  srand(chrono::steady_clock::now().time_since_epoch().count());
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
}
int main() {
  IO();
  long long int n;
  string s;
  cin >> s;
  n = s.length();
  if (n < 26) {
    cout << -1;
  } else {
    int st = 0;
    for (__typeof(26) i = (0) - ((0) > (26)); i != (26) - ((0) > (26));
         i += 1 - 2 * ((0) > (26))) {
      int found = 0;
      char want = 'a' + i;
      for (__typeof(n) j = (st) - ((st) > (n)); j != (n) - ((st) > (n));
           j += 1 - 2 * ((st) > (n))) {
        if (s[j] == want) {
          if (!found) {
            found = 1;
            st = j + 1;
          } else {
            if (want < 'z') s[j]++;
          }
        }
      }
      if (!found) {
        cout << -1;
        return 0;
      }
    }
    cout << s;
  }
  return 0;
}
