Given an array of strings `strs`, return the length of the longest uncommon subsequence between them. If the longest uncommon subsequence does not exist, return `-1`.

An uncommon subsequence between an array of strings is a string that is a subsequence of one string but not the others.

A subsequence of a string `s` is a string that can be obtained after deleting any number of characters from `s`.

- For example, `"abc"` is a subsequence of `"aebdc"` because you can delete the underlined characters in `"aebdc"` to get `"abc"`. Other subsequences of `"aebdc"` include `"aebdc"`, `"aeb"`, and `""` (empty string).

Example 1:

    Input: strs = ["aba","cdc","eae"]
    Output: 3

Example 2:

    Input: strs = ["aaa","aaa","aa"]
    Output: -1

Constraints:

- `2 <= strs.length <= 50`
- `1 <= strs[i].length <= 10`
- `strs[i]` consists of lowercase English letters.