#include <bits/stdc++.h>
using namespace std;
using namespace std::chrono;
long long dist(char ch, long long x) {
  long long y = ch - 'a';
  if (y > x) return INT_MAX;
  return x - y;
}
signed main() {
  string s;
  cin >> s;
  long long n = s.length();
  if (n < 26) {
    cout << "-1\n";
    return 0;
  }
  long long j = 0;
  string s2 = "abcdefghijklmnopqrstuvwxyz";
  for (long long i = 0; i < n; i++) {
    if (s[i] <= s2[j]) {
      s[i] = s2[j];
      j++;
    }
    if (j >= 26) break;
  }
  if (j < 26) {
    cout << "-1\n";
    return 0;
  }
  cout << s << "\n";
}
