HackerRank: string - Game Throne https://www.hackerrank.com/challenges/game-of-thrones

GameThrone.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace GameOfThrones
{
    class Program
    {
        /*
         * GameOfThrones
         * https://www.hackerrank.com/challenges/game-of-thrones
         * 
         * 
         */
        static void Main(string[] args)
        {
            string s = Console.ReadLine();

            if (canBePalindrome(s))
                Console.WriteLine("YES"); 
            else
                Console.WriteLine("NO"); 
        }

        /*
         * Determine whether any anagram of the string can be a palindrome or  not
         * 
         * length of string >=1 
         * if the string has only one char - odd number 
         * string length %2 == 0, all should be even number
         * string length %2 == 1, only one char's count is odd number 
         * 
         * lower case English letter - 26 or 256
         */

        public static bool canBePalindrome(string s)
        {
            if (s == null || s.Length == 0)
                return false;

            int MaxSize = 256; 
            int[] countA = new int[MaxSize]; 

            for(int i =0; i< s.Length; i++)
            {
                countA[s[i]]++; 
            }

            int oddCount = 0; 

            for(int i = 0; i< MaxSize; i++)
            {
                if(isLowerCaseEnglishLetter(i) && countA[i] %2 ==1)  // bug: not s[i], should be i
                {
                    oddCount++;
                    if (oddCount > 1)
                        return false; 
                }
            }

            return true; 
        }

        private static bool isLowerCaseEnglishLetter(int value)
        {
            int n = value-'a';
            if (n >= 0 && n < 26)
                return true;
            else
                return false; 
        }
    }
}