Word Pattern
<p>Given a <code>pattern</code> and a string <code>s</code>, find if <code>s</code>&nbsp;follows the same pattern.</p>

<p>Here <b>follow</b> means a full match, such that there is a bijection between a letter in <code>pattern</code> and a <b>non-empty</b> word in <code>s</code>. Specifically:</p>

<ul>
	<li>Each letter in <code>pattern</code> maps to <strong>exactly</strong> one unique word in <code>s</code>.</li>
	<li>Each unique word in <code>s</code> maps to <strong>exactly</strong> one letter in <code>pattern</code>.</li>
	<li>No two letters map to the same word, and no two words map to the same letter.</li>
</ul>

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

<div class="example-block">
<p><strong>Input:</strong> <span class="example-io">pattern = &quot;abba&quot;, s = &quot;dog cat cat dog&quot;</span></p>

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

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

<p>The bijection can be established as:</p>

<ul>
	<li><code>&#39;a&#39;</code> maps to <code>&quot;dog&quot;</code>.</li>
	<li><code>&#39;b&#39;</code> maps to <code>&quot;cat&quot;</code>.</li>
</ul>
</div>

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

<div class="example-block">
<p><strong>Input:</strong> <span class="example-io">pattern = &quot;abba&quot;, s = &quot;dog cat cat fish&quot;</span></p>

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

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

<div class="example-block">
<p><strong>Input:</strong> <span class="example-io">pattern = &quot;aaaa&quot;, s = &quot;dog cat cat dog&quot;</span></p>

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

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

<ul>
	<li><code>1 &lt;= pattern.length &lt;= 300</code></li>
	<li><code>pattern</code> contains only lower-case English letters.</li>
	<li><code>1 &lt;= s.length &lt;= 3000</code></li>
	<li><code>s</code> contains only lowercase English letters and spaces <code>&#39; &#39;</code>.</li>
	<li><code>s</code> <strong>does not contain</strong> any leading or trailing spaces.</li>
	<li>All the words in <code>s</code> are separated by a <strong>single space</strong>.</li>
</ul>
Hash Table; String
func wordPattern(pattern string, s string) bool {
	ws := strings.Split(s, " ")
	if len(ws) != len(pattern) {
		return false
	}
	d1 := map[rune]string{}
	d2 := map[string]rune{}
	for i, a := range pattern {
		b := ws[i]
		if v, ok := d1[a]; ok && v != b {
			return false
		}
		if v, ok := d2[b]; ok && v != a {
			return false
		}
		d1[a] = b
		d2[b] = a
	}
	return true
}