<p>You are given an integer <code>n</code>.</p>

<p>A string <code>s</code> is called <strong>good </strong>if it contains only lowercase English characters <strong>and</strong> it is possible to rearrange the characters of <code>s</code> such that the new string contains <code>&quot;leet&quot;</code> as a <strong>substring</strong>.</p>

<p>For example:</p>

<ul>
	<li>The string <code>&quot;lteer&quot;</code> is good because we can rearrange it to form <code>&quot;leetr&quot;</code> .</li>
	<li><code>&quot;letl&quot;</code> is not good because we cannot rearrange it to contain <code>&quot;leet&quot;</code> as a substring.</li>
</ul>

<p>Return <em>the <strong>total</strong> number of good strings of length </em><code>n</code>.</p>

<p>Since the answer may be large, return it <strong>modulo </strong><code>10<sup>9</sup> + 7</code>.</p>

<p>A <strong>substring</strong> is a contiguous sequence of characters within a string.</p>

<div class="notranslate" style="all: initial;">&nbsp;</div>

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

<pre>
<strong>Input:</strong> n = 4
<strong>Output:</strong> 12
<strong>Explanation:</strong> The 12 strings which can be rearranged to have &quot;leet&quot; as a substring are: &quot;eelt&quot;, &quot;eetl&quot;, &quot;elet&quot;, &quot;elte&quot;, &quot;etel&quot;, &quot;etle&quot;, &quot;leet&quot;, &quot;lete&quot;, &quot;ltee&quot;, &quot;teel&quot;, &quot;tele&quot;, and &quot;tlee&quot;.
</pre>

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

<pre>
<strong>Input:</strong> n = 10
<strong>Output:</strong> 83943898
<strong>Explanation:</strong> The number of strings with length 10 which can be rearranged to have &quot;leet&quot; as a substring is 526083947580. Hence the answer is 526083947580 % (10<sup>9</sup> + 7) = 83943898.
</pre>

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

<ul>
	<li><code>1 &lt;= n &lt;= 10<sup>5</sup></code></li>
</ul>

class Solution:
    def stringCount(self, n: int) -> int:
        # s = defaultdict(lambda: 0)
        # mod = 10**9 + 7

        # def rec(i: int) -> int:
        #     if s['e'] >= 2 and s['l'] and s['t']:
        #         return 26**(n-i) % mod
        #     if i == n:
        #         return 0
        #     count = 0
        #     for o in range(ord('a'), ord('z') + 1):
        #         c = chr(o)
        #         if c in ('l', 'e', 't'):
        #             s[c] += 1
        #         count = (count + rec(i+1)) % mod
        #         s[c] -= 1
        #     return count
        # return rec(0)

        mod = 10**9 + 7
        count = [[[[0 for _ in range(2)] for _ in range(2)] for _ in range(3)] for _ in range(n+1)]
        count[n][0][0][0] = 1

        for i in range(n-1, -1, -1):
            for e in range(3):
                for l in range(2):
                    for t in range(2):
                        avail = sum([e == 0, l == 0, t == 0])
                        count[i][e][l][t] = ((23 + avail) * count[i+1][e][l][t]) % mod
                        
                        if e > 0:
                            count[i][e][l][t] = (count[i][e][l][t] + count[i+1][e-1][l][t]) % mod
                        if l > 0:
                            count[i][e][l][t] = (count[i][e][l][t] + count[i+1][e][l-1][t]) % mod
                        if t > 0:
                            count[i][e][l][t] = (count[i][e][l][t] + count[i+1][e][l][t-1]) % mod
        return count[0][2][1][1]
149100