leetcode125

public class Solution {
    Stack<char> S = new Stack<char>();
        Queue<char> Q = new Queue<char>();
        public bool IsPalindrome(string s)
        {
            if (s.Length == )
            {
                return true;
            }
            s = s.ToLower();
            foreach (var c in s)
            {
                if ((c >= 'a' && c <= 'z') || (c >= '' && c <= ''))
                {
                    S.Push(c);
                    Q.Enqueue(c);
                }
            }

            while (S.Count > )
            {
                var ss = S.Pop();
                var qq = Q.Dequeue();
                if (ss != qq)
                {
                    return false;
                }
            }
            return true;
        }
}

https://leetcode.com/problems/valid-palindrome/#/description