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
function countOfSubstrings(word: string, k: number): number {
    const f = (k: number): number => {
        let ans = 0;
        let l = 0,
            x = 0;
        const cnt = new Map<string, number>();

        const vowel = (c: string): boolean => {
            return c === 'a' || c === 'e' || c === 'i' || c === 'o' || c === 'u';
        };

        for (const c of word) {
            if (vowel(c)) {
                cnt.set(c, (cnt.get(c) || 0) + 1);
            } else {
                x++;
            }

            while (x >= k && cnt.size === 5) {
                const d = word[l++];
                if (vowel(d)) {
                    cnt.set(d, cnt.get(d)! - 1);
                    if (cnt.get(d) === 0) {
                        cnt.delete(d);
                    }
                } else {
                    x--;
                }
            }
            ans += l;
        }

        return ans;
    };

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