Class Solution
java.lang.Object
g2201_2300.s2266_count_number_of_texts.Solution
2266 - Count Number of Texts.<p>Medium</p>
<p>Alice is texting Bob using her phone. The <strong>mapping</strong> of digits to letters is shown in the figure below.</p>
<p><img src="https://assets.leetcode.com/uploads/2022/03/15/1200px-telephone-keypad2svg.png" alt="" /></p>
<p>In order to <strong>add</strong> a letter, Alice has to <strong>press</strong> the key of the corresponding digit <code>i</code> times, where <code>i</code> is the position of the letter in the key.</p>
<ul>
<li>For example, to add the letter <code>'s'</code>, Alice has to press <code>'7'</code> four times. Similarly, to add the letter <code>'k'</code>, Alice has to press <code>'5'</code> twice.</li>
<li>Note that the digits <code>'0'</code> and <code>'1'</code> do not map to any letters, so Alice <strong>does not</strong> use them.</li>
</ul>
<p>However, due to an error in transmission, Bob did not receive Alice’s text message but received a <strong>string of pressed keys</strong> instead.</p>
<ul>
<li>For example, when Alice sent the message <code>"bob"</code>, Bob received the string <code>"2266622"</code>.</li>
</ul>
<p>Given a string <code>pressedKeys</code> representing the string received by Bob, return <em>the <strong>total number of possible text messages</strong> Alice could have sent</em>.</p>
<p>Since the answer may be very large, return it <strong>modulo</strong> <code>10<sup>9</sup> + 7</code>.</p>
<p><strong>Example 1:</strong></p>
<p><strong>Input:</strong> pressedKeys = “22233”</p>
<p><strong>Output:</strong> 8</p>
<p><strong>Explanation:</strong></p>
<p>The possible text messages Alice could have sent are:</p>
<p>“aaadd”, “abdd”, “badd”, “cdd”, “aaae”, “abe”, “bae”, and “ce”.</p>
<p>Since there are 8 possible messages, we return 8.</p>
<p><strong>Example 2:</strong></p>
<p><strong>Input:</strong> pressedKeys = “222222222222222222222222222222222222”</p>
<p><strong>Output:</strong> 82876089</p>
<p><strong>Explanation:</strong> There are 2082876103 possible text messages Alice could have sent.</p>
<p>Since we need to return the answer modulo 10<sup>9</sup> + 7, we return 2082876103 % (10<sup>9</sup> + 7) = 82876089.</p>
<p><strong>Constraints:</strong></p>
<ul>
<li><code>1 <= pressedKeys.length <= 10<sup>5</sup></code></li>
<li><code>pressedKeys</code> only consists of digits from <code>'2'</code> - <code>'9'</code>.</li>
</ul>
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Solution
public Solution()
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countTexts
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