mirror of
https://gitee.com/coder-xiaomo/leetcode-problemset
synced 2025-01-10 18:48:13 +08:00
15 lines
399 B
HTML
15 lines
399 B
HTML
<p>Write a method to count the number of 2s that appear in all the numbers between 0 and n (inclusive).</p>
|
|
|
|
|
|
|
|
<p><strong>Example:</strong></p>
|
|
|
|
|
|
|
|
<pre>
|
|
|
|
<strong>Input: </strong>25
|
|
|
|
<strong>Output: </strong>9
|
|
|
|
<strong>Explanation: </strong>(2, 12, 20, 21, 22, 23, 24, 25)(Note that 22 counts for two 2s.)</pre>
|
|
|
|
|
|
|
|
<p>Note:</p>
|
|
|
|
|
|
|
|
<ul>
|
|
|
|
<li><code>n <= 10^9</code></li>
|
|
|
|
</ul>
|
|
|