<p>A string <code>s</code> can be partitioned into groups of size <code>k</code> using the following procedure:</p>
<ul>
<li>The first group consists of the first <code>k</code> characters of the string, the second group consists of the next <code>k</code> characters of the string, and so on. Each character can be a part of <strong>exactly one</strong> group.</li>
<li>For the last group, if the string <strong>does not</strong> have <code>k</code> characters remaining, a character <code>fill</code> is used to complete the group.</li>
</ul>
<p>Note that the partition is done so that after removing the <code>fill</code> character from the last group (if it exists) and concatenating all the groups in order, the resultant string should be <code>s</code>.</p>
<p>Given the string <code>s</code>, the size of each group <code>k</code> and the character <code>fill</code>, return <em>a string array denoting the <strong>composition of every group</strong></em><code>s</code><em> has been divided into, using the above procedure</em>.</p>