<p>You are given a list of strings of the <strong>same length</strong><code>words</code> and a string <code>target</code>.</p>
<p>Your task is to form <code>target</code> using the given <code>words</code> under the following rules:</p>
<ul>
<li><code>target</code> should be formed from left to right.</li>
<li>To form the <code>i<sup>th</sup></code> character (<strong>0-indexed</strong>) of <code>target</code>, you can choose the <code>k<sup>th</sup></code> character of the <code>j<sup>th</sup></code> string in <code>words</code> if <code>target[i] = words[j][k]</code>.</li>
<li>Once you use the <code>k<sup>th</sup></code> character of the <code>j<sup>th</sup></code> string of <code>words</code>, you <strong>can no longer</strong> use the <code>x<sup>th</sup></code> character of any string in <code>words</code> where <code>x <= k</code>. In other words, all characters to the left of or at index <code>k</code> become unusuable for every string.</li>
<li>Repeat the process until you form the string <code>target</code>.</li>
</ul>
<p><strong>Notice</strong> that you can use <strong>multiple characters</strong> from the <strong>same string</strong> in <code>words</code> provided the conditions above are met.</p>
<p>Return <em>the number of ways to form <code>target</code> from <code>words</code></em>. Since the answer may be too large, return it <strong>modulo</strong><code>10<sup>9</sup> + 7</code>.</p>
