Give a binary string `s`, return the number of non-empty substrings that have the same number of `0`'s and `1`'s, and all the `0`'s and all the `1`'s in these substrings are grouped consecutively.

Substrings that occur multiple times are counted the number of times they occur.

Example 1:

    Input: s = "00110011"
    Output: 6
    Explanation: There are 6 substrings that have equal number of consecutive 1's and 0's: "0011", "01", "1100", "10", "0011", and "01".
    Notice that some of these substrings repeat and are counted the number of times they occur.
    Also, "00110011" is not a valid substring because all the 0's (and 1's) are not grouped together.

Example 2:

    Input: s = "10101"
    Output: 4
    Explanation: There are 4 substrings: "10", "01", "10", "01" that have equal number of consecutive 1's and 0's.

Constraints:

- `1 <= s.length <= 105`
- `s[i]` is either `'0'` or `'1'`.