using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.Text;
using System.Text.RegularExpressions;
using System.Linq;
using System.IO;

class Program
{
    static private Magatro M = new Magatro();
    static private void Main(string[]args)
    {
        M.Scan();
        M.Solve();
    }
}

public class Scanner
{
    private string[] S;
    private int Index;
    private char Separator;
    public Scanner(char separator = ' ')
    {
        Index = 0;
        Separator = separator;
    }
    private string[] Line()
    {
        return Console.ReadLine().Split(Separator);
    }
    public string Next()
    {
        string result;
        if (S == null || Index >= S.Length)
        {
            S = Line();
            Index = 0;
        }
        result = S[Index];
        Index++;
        return result;
    }
    public int NextInt()
    {
        return int.Parse(Next());
    }
    public double NextDouble()
    {
        return double.Parse(Next());
    }
    public long NextLong()
    {
        return long.Parse(Next());
    }
}

public class Magatro
{
    private string S;
    public void Scan()
    {
        Scanner sc = new Scanner();
        S = sc.Next();
    }
  public void Solve()
    {
        int ans = 1;
        for(int left = 0; left < S.Length-1; left++)
        {
            for(int right = left+1; right < S.Length; right++)
            {
                if (Kaibun(left, right))
                {
                    ans = Math.Max(ans, right - left + 1);
                }
            }
        }
        Console.WriteLine(ans);
    }
    private bool Kaibun(int left ,int right)
    {
        if (left == 0 && right == S.Length - 1) return false;
        int loop = (right - left+1) / 2;
        for(int i = 0; i < loop; i++)
        {
            if (S[left + i] != S[right - i]) return false;
        }
        return true;
    }
}