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

namespace No273
{
    class Program
    {
        static void Main(string[] args)
        {
            string sentence;
            int maxLength = 0;

            Console.WriteLine("回文判定");
            Console.Write(" 単語 = ");
            sentence=Console.ReadLine();

            for (int i = 0; i < sentence.Length; i++)
            {
                int num;
                string temp = sentence.Substring(i);
                num = SearchPalindrome(temp);
                if (maxLength < num)
                    maxLength = num;
            }

            Console.WriteLine(" 単語に含まれる回文の最大値 = {0}", maxLength);
        }

        static int SearchPalindrome(string sentence)
        {
            if (sentence.Length <= 1)
                return sentence.Length;

            if (sentence[0] == sentence[sentence.Length - 1])
                return SearchPalindrome(sentence.Remove(sentence.Length - 1).Substring(1)) + 2;
            else
                return SearchPalindrome(sentence.Remove(sentence.Length - 1));
        }
    }
}