#include <bits/stdc++.h>
using namespace std;
long long a[1005], s[1005];
int main() {
  ios_base::sync_with_stdio(0);
  string s;
  cin >> s;
  string s2 = "abcdefghijklmnopqrstuvwxyz";
  if (s.size() < 26) {
    cout << -1;
    return 0;
  }
  long long k = 0;
  for (int i = 0; i < s.size(); i++) {
    if (s[i] <= s2[k] && k < 26) {
      s[i] = s2[k];
      k++;
    } else {
      continue;
    }
  }
  if (k >= 26) {
    cout << s;
  } else {
    cout << -1;
  }
  return 0;
}
