Count of Substrings Containing Every Vowel and K Consonants I
<p>You are given a string <code>word</code> and a <strong>non-negative</strong> integer <code>k</code>.</p>

<p>Return the total number of <span data-keyword="substring-nonempty">substrings</span> of <code>word</code> that contain every vowel (<code>&#39;a&#39;</code>, <code>&#39;e&#39;</code>, <code>&#39;i&#39;</code>, <code>&#39;o&#39;</code>, and <code>&#39;u&#39;</code>) <strong>at least</strong> once and <strong>exactly</strong> <code>k</code> consonants.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<div class="example-block">
<p><strong>Input:</strong> <span class="example-io">word = &quot;aeioqq&quot;, k = 1</span></p>

<p><strong>Output:</strong> <span class="example-io">0</span></p>

<p><strong>Explanation:</strong></p>

<p>There is no substring with every vowel.</p>
</div>

<p><strong class="example">Example 2:</strong></p>

<div class="example-block">
<p><strong>Input:</strong> <span class="example-io">word = &quot;aeiou&quot;, k = 0</span></p>

<p><strong>Output:</strong> <span class="example-io">1</span></p>

<p><strong>Explanation:</strong></p>

<p>The only substring with every vowel and zero consonants is <code>word[0..4]</code>, which is <code>&quot;aeiou&quot;</code>.</p>
</div>

<p><strong class="example">Example 3:</strong></p>

<div class="example-block">
<p><strong>Input:</strong> <span class="example-io">word = &quot;</span>ieaouqqieaouqq<span class="example-io">&quot;, k = 1</span></p>

<p><strong>Output:</strong> 3</p>

<p><strong>Explanation:</strong></p>

<p>The substrings with every vowel and one consonant are:</p>

<ul>
	<li><code>word[0..5]</code>, which is <code>&quot;ieaouq&quot;</code>.</li>
	<li><code>word[6..11]</code>, which is <code>&quot;qieaou&quot;</code>.</li>
	<li><code>word[7..12]</code>, which is <code>&quot;ieaouq&quot;</code>.</li>
</ul>
</div>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>5 &lt;= word.length &lt;= 250</code></li>
	<li><code>word</code> consists only of lowercase English letters.</li>
	<li><code>0 &lt;= k &lt;= word.length - 5</code></li>
</ul>
Hash Table; String; Sliding Window
class Solution:
    def countOfSubstrings(self, word: str, k: int) -> int:
        def f(k: int) -> int:
            cnt = Counter()
            ans = l = x = 0
            for c in word:
                if c in "aeiou":
                    cnt[c] += 1
                else:
                    x += 1
                while x >= k and len(cnt) == 5:
                    d = word[l]
                    if d in "aeiou":
                        cnt[d] -= 1
                        if cnt[d] == 0:
                            cnt.pop(d)
                    else:
                        x -= 1
                    l += 1
                ans += l
            return ans

        return f(k) - f(k + 1)
