【LeetCode】5. 最长回文子串

public string LongestPalindrome(string s)
{
    if (string.IsNullOrEmpty(s) || s.Length <= 1) return s;

    var result = string.Empty;

    var dp = new bool[s.Length, s.Length];

    for (int i = s.Length - 1; i >= 0; i--)
    {
        for (int k = i; k < s.Length; k++)
        {
            dp[i, k] = s[i] == s[k] && (k - i < 2 || dp[i + 1, k - 1]);

            if (dp[i, k] && (k - i + 1) > result.Length)
            {
                result = s.Substring(i, k - i + 1);
            }
        }
    }
    return result;
}