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+<h2><a href="https://leetcode.com/problems/detect-capital/">520. Detect Capital</a></h2><h3>Easy</h3><hr><div><p>We define the usage of capitals in a word to be right when one of the following cases holds:</p>
+
+<ul>
+	<li>All letters in this word are capitals, like <code>"USA"</code>.</li>
+	<li>All letters in this word are not capitals, like <code>"leetcode"</code>.</li>
+	<li>Only the first letter in this word is capital, like <code>"Google"</code>.</li>
+</ul>
+
+<p>Given a string <code>word</code>, return <code>true</code> if the usage of capitals in it is right.</p>
+
+<p>&nbsp;</p>
+<p><strong class="example">Example 1:</strong></p>
+<pre><strong>Input:</strong> word = "USA"
+<strong>Output:</strong> true
+</pre><p><strong class="example">Example 2:</strong></p>
+<pre><strong>Input:</strong> word = "FlaG"
+<strong>Output:</strong> false
+</pre>
+<p>&nbsp;</p>
+<p><strong>Constraints:</strong></p>
+
+<ul>
+	<li><code>1 &lt;= word.length &lt;= 100</code></li>
+	<li><code>word</code> consists of lowercase and uppercase English letters.</li>
+</ul>
+</div>
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