<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:
    bool isPalindrome(string s) {
        int n = s.size();
        for (int i = 0; i < n / 2; ++i) {
            if (s[i] != s[n - i - 1]) return false;
        }
        return true;
    }

    vector<long long> generatePalindromes(int maxLen) {
        vector<long long> palindromes;
        for (int len = 1; len <= maxLen; ++len) {
            for (int half = pow(10, (len - 1) / 2); half < pow(10, (len + 1) / 2); ++half) {
                string halfStr = to_string(half);
                string fullStr = halfStr + string(halfStr.rbegin() + (len % 2), halfStr.rend());
                palindromes.push_back(stoll(fullStr));
            }
        }
        return palindromes;
    }

    int superpalindromesInRange(string left, string right) {
        long long l = stoll(left), r = stoll(right);
        int maxLen = 9; // For palindromic roots of up to 10^18, 9 digits is sufficient.
        vector<long long> palindromes = generatePalindromes(maxLen);
        int ans = 0;

        for (auto& p : palindromes) {
            long long superPalindrome = p * p;
            if (superPalindrome > r) break;
            if (superPalindrome >= l && isPalindrome(to_string(superPalindrome))) {
                ans++;
            }
        }
        return ans;
    }
};

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