#include <bits/stdc++.h>
using namespace std;
const int MAXN = 1e5 + 5;
char s[MAXN];
int main() {
  scanf("%s", s);
  int len = strlen(s);
  if (len <= 25) {
    cout << "-1" << endl;
    return 0;
  }
  int ans = 97;
  int a[27];
  memset(a, 0, sizeof(a));
  int cur = 0;
  for (int i = 0; i < len; i++) {
    if (cur == 26) break;
    if (s[i] <= ans) {
      ans++;
      a[cur++] = i;
    }
  }
  if (a[25]) {
    int num = 0;
    for (int i = 0; i < len; i++) {
      if (a[num] == i) {
        printf("%c", num + 97);
        num++;
      } else {
        printf("%c", s[i]);
      }
    }
    printf("\n");
  } else
    printf("-1\n");
  return 0;
}
