<p>Given two <strong>version strings</strong>, <code>version1</code> and <code>version2</code>, compare them. A version string consists of <strong>revisions</strong> separated by dots <code>'.'</code>. The <strong>value of the revision</strong> is its <strong>integer conversion</strong> ignoring leading zeros.</p>
<p>To compare version strings, compare their revision values in <strong>left-to-right order</strong>. If one of the version strings has fewer revisions, treat the missing revision values as <code>0</code>.</p>
<li><code>version1</code> and <code>version2</code> only contain digits and <code>'.'</code>.</li>
<li><code>version1</code> and <code>version2</code> <strong>are valid version numbers</strong>.</li>
<li>All the given revisions in <code>version1</code> and <code>version2</code> can be stored in a <strong>32-bit integer</strong>.</li>