<p>Let&#39;s say a positive integer is a <strong>super-palindrome</strong> if it is a palindrome, and it is also the square of a palindrome.</p>

<p>Given two positive integers <code>left</code> and <code>right</code> represented as strings, return <em>the number of <strong>super-palindromes</strong> integers in the inclusive range</em> <code>[left, right]</code>.</p>

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

<pre>
<strong>Input:</strong> left = &quot;4&quot;, right = &quot;1000&quot;
<strong>Output:</strong> 4
<strong>Explanation</strong>: 4, 9, 121, and 484 are superpalindromes.
Note that 676 is not a superpalindrome: 26 * 26 = 676, but 26 is not a palindrome.
</pre>

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

<pre>
<strong>Input:</strong> left = &quot;1&quot;, right = &quot;2&quot;
<strong>Output:</strong> 1
</pre>

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

<ul>
	<li><code>1 &lt;= left.length, right.length &lt;= 18</code></li>
	<li><code>left</code> and <code>right</code> consist of only digits.</li>
	<li><code>left</code> and <code>right</code> cannot have leading zeros.</li>
	<li><code>left</code> and <code>right</code> represent integers in the range <code>[1, 10<sup>18</sup> - 1]</code>.</li>
	<li><code>left</code> is less than or equal to <code>right</code>.</li>
</ul>

class Solution {
public:
    int superpalindromesInRange(string left, string right) {
        long long min_num = stoll(left), max_num = stoll(right);
        vector<long long> palindromes(9);
        iota(begin(palindromes), end(palindromes), 1ll);
        for (int i = 1; i < 10000; ++i) {
            string left = to_string(i), right = left;
            reverse(begin(right), end(right));
            palindromes.push_back(stoll(left + right));
            for (int mid = 0; mid <= 9; ++mid) {
                palindromes.push_back(stoll(left + to_string(mid) + right));
            }
        }
        int res = 0;
        for (const auto& num : palindromes) {
            long long square_num = num * num;
            if (square_num >= min_num && square_num <= max_num && IsPalindrome(to_string(square_num))) {
                ++res;
            }
        }
        return res;
    }
private:
    bool IsPalindrome(string&& num) {
        for (int i = 0; i < num.size() / 2; ++i) {
            if (num[i] != num[num.size() - i - 1])
                return false;
        }
        return true;
    }
};
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