Given a string word, return the number of substrings of word that are vowel substrings.

A substring of word is considered a vowel substring if both of the following are true:

1. Every character in the substring is a vowel from the set {a, e, i, o, u}.

2. The substring contains each of the five vowels a, e, i, o, and u at least once.

Constraints:

• $1 \leq$ word.length $\leq 100$

• word consists of lowercase English letters only.

Input: word = "aeiouu"-str
Output: 2-int
Explanation: The vowel-only substrings that contain all five vowels are "aeiou" (indices 0–4) and "aeiouu" (indices 0–5). Any substring starting at index 1 cannot include 'a', so it cannot contain all five vowels.

Input: word = "unicornarihan"-str
Output: 0-int
Explanation: Although the string contains vowels, there is no contiguous substring made up only of vowels that also includes all five vowels a,e,i,o,u.

Input: word = "cuaieuouac"-str
Output: 7-int
Explanation: The maximal vowel-only block is "uaieuoua" (indices 1–8). Within it, the substrings containing all five vowels are "uaieuo", "uaieuou", "uaieuoua" starting at index 1 (3); "aieuou", "aieuoua" starting at index 2 (2); "ieuoua" starting at index 3 (1); and "euoua" starting at index 4 (1), for a total of 3 + 2 + 1 + 1 = 7.

Input: word = "aaaaaeiou"-str
Output: 5-int
Explanation: The entire string is vowel-only. Any substring that ends at the last character and starts at one of the five 'a' positions (indices 0–4) contains all five vowels, giving 5 such substrings: "aaaaaeiou", "aaaaeiou", "aaaeiou", "aaeiou", and "aeiou".

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