leetcode479

public class Solution
    {
        public int LargestPalindrome(int n)
        {
            if (n == ) return ;
            int max = (int)Math.Pow(, n) - ;
            for (int v = max - ; v > max / ; v--)
            {
                StringBuilder sb = new StringBuilder();
                foreach (var c in v.ToString().Reverse())
                {
                    sb.Append(c);
                }
                long u = Convert.ToInt64(v.ToString() + sb.ToString());
                for (long x = max; x * x >= u; x--)
                    if (u % x == )
                        return (int)(u % );
            }
            return ;
        }
    }

https://leetcode.com/problems/largest-palindrome-product/description/