<p>Given a string <code>s</code>, return <em>the last substring of</em> <code>s</code> <em>in lexicographical order</em>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> s = &quot;abab&quot;
<strong>Output:</strong> &quot;bab&quot;
<strong>Explanation:</strong> The substrings are [&quot;a&quot;, &quot;ab&quot;, &quot;aba&quot;, &quot;abab&quot;, &quot;b&quot;, &quot;ba&quot;, &quot;bab&quot;]. The lexicographically maximum substring is &quot;bab&quot;.
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> s = &quot;leetcode&quot;
<strong>Output:</strong> &quot;tcode&quot;
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= s.length &lt;= 4 * 10<sup>5</sup></code></li>
	<li><code>s</code> contains only lowercase English letters.</li>
</ul>

class Solution:
    def lastSubstring(self, s: str) -> str:
        c = max(s)
        substrs = s.split(c)

        i = len(substrs) - 2
        while i >= 1:
            if substrs[i] == '':
                substrs.pop(i)
                substrs[i] = c + substrs[i]
            i -= 1

        substr_idx = substrs[1:].index(sorted(substrs[1:])[-1]) + 1
        split_idx = sum([len(substr) for substr in substrs][:substr_idx]) + substr_idx - 1

        if substrs[-1] == '' and len(substrs) > 2:
            if c + substrs[-2] + c > s[split_idx:]:
                return c + substrs[-2] + c
        return s[split_idx:]
915