Given a string `s`, check if it can be constructed by taking a substring of it and appending multiple copies of the substring together.

Example 1:

    Input: s = "abab"
    Output: true
    Explanation: It is the substring "ab" twice.

Example 2:

    Input: s = "aba"
    Output: false

Example 3:

    Input: s = "abcabcabcabc"
    Output: true
    Explanation: It is the substring "abc" four times or the substring "abcabc" twice.

Constraints:

- `1 <= s.length <= 104`
- `s` consists of lowercase English letters.