using LIB;
using System;
using System.Linq;
using System.Text;
using System.Collections.Generic;

class Program
{
    static bool loop(string s)
    {
        int cnt = s.Count();
        bool ret = true;
        for (int i = 0; i < cnt / 2; i++)
        {
            if (s[i] != s[cnt - 1 - i])
            {
                ret = false;
                break;
            } 
        }
        return ret;
    }
    static void Main(string[] args)
    {
        string s = io.r<string>();
        int len = s.Count();
        int output = 0;
        for (int i = 0; i < len; i++)
        {
            for (int j = 0; j < i; j++)
            {
                string ss = s.Substring(0, i - j);
                if (loop(ss))
                {
                    if (output < ss.Count() && ss.Count() != len)
                    {
                        output = ss.Count();
                    }
                }
            }
            for (int j = i + 1; j <= len; j++)
            {
                string ss = s.Substring(i, j - i);
                if (loop(ss))
                {
                    if (output < ss.Count() && ss.Count() != len)
                    {
                        output = ss.Count();
                    }
                }
            }
        }
        io.w(output);
        io.wflush();
    }
}

namespace LIB
{
    public class io
    {
        private const int WMAX = 1000;
        private static StringBuilder S = new StringBuilder();
        public static T r<T>() { return util.parse<T>(r()); }
        public static T[] r<T>(char s = ' ') { return r().Split(s).Select(util.parse<T>).ToArray(); }
        public static T[] r<T>(int l) { T[] r = new T[l]; for (int i = 0; i < l; i++) { r[i] = r<T>(); } return r; }
        public static T[][] r<T>(int l, char s = ' ') { T[][] r = new T[l][]; for (int i = 0; i < l; i++) { r[i] = r<T>(s); } return r; }
        private static string r() { return Console.ReadLine(); }
        public static void w(object v, bool lf = true) { S.Append(util.parse<string>(v)); if (lf == true) { S.Append('\n'); } if (S.Length >= WMAX) { wflush(); } }
        public static void wflush() { Console.Write(S.ToString()); S.Clear(); }
    }
    public class util
    {
        public static T parse<T>(object value) { return (T)(Convert.ChangeType(value, typeof(T))); }
    }
    public class memo<Key, Result>
    {
        private Dictionary<Key, Result> R;
        public memo() { R = new Dictionary<Key, Result>(); }
        public Result exec(Key k, Func<Key, Result> f) { Result r; if (R.ContainsKey(k)) { r = R[k]; } else { r = f(k); R.Add(k, r); } return r; }
    }
}