#include <bits/stdc++.h>
using namespace std;
const int N = (int)(1e7);
int main() {
  bool ok = false;
  string a;
  cin >> a;
  if (a.size() < 26)
    return cout << -1 << endl, 0;
  else {
    string b = "abcdefghijklmnopqrstuvwxyz";
    int j = 0;
    for (int i = 0; i < a.size() && !ok; i++) {
      if (a[i] <= b[j]) a[i] = b[j++];
      if (j == 26) ok = true;
    }
  }
  ok ? cout << a << endl : cout << -1 << endl;
  return 0;
}
