Given a string `s`, return `true` if `s` is a good string, or `false` otherwise.

A string `s` is good if all the characters that appear in `s` have the same number of occurrences (i.e., the same frequency).

Example 1:

    Input: s = "abacbc"
    Output: true
    Explanation: The characters that appear in s are 'a', 'b', and 'c'. All characters occur 2 times in s.

Example 2:

    Input: s = "aaabb"
    Output: false
    Explanation: The characters that appear in s are 'a' and 'b'.
    'a' occurs 3 times while 'b' occurs 2 times, which is not the same number of times.

Constraints:

- `1 <= s.length <= 1000`
- `s` consists of lowercase English letters.