using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.Numerics;
using System.Text;
using static System.Math;
using static System.Linq.Enumerable;
using static Extentions;
using static System.Console;

public static class Program
{
    #region Scanners
    static Scanner _scanner;
    static char C => _scanner.NextChar();
    static string S => _scanner.NextString();
    static int I => _scanner.NextInt();
    static long L => _scanner.NextLong();
    static BigInteger B => _scanner.NextBigInteger();
    static double D => _scanner.NextDouble();
    static decimal M => _scanner.NextDecimal();
    #endregion

    public static void Solve()
    {
        var s = S;
        var ans = 0;

        for (var i = 0; i < s.Length; i++)
        {
            var l = Min(i, s.Length - i - 1);

            var cnt1 = 0;
            for (var j = 1; j <= l; j++)
                if (s[i - j] == s[i + j]) cnt1++;
            ans = Max(ans, cnt1);

            var cnt2 = 0;
            for (var j = 1; j <= l; j++)
                if (s[i - j] == s[i + j - 1]) cnt2++;
            ans = Max(ans, cnt2);
        }

        WriteLine(ans * 2 + 1);
    }

    public static void Main()
    {
        Console.SetOut(new StreamWriter(Console.OpenStandardOutput())
        {
            NewLine = "\n",
#if DEBUG
            AutoFlush = true,
#else
            AutoFlush = false,
#endif
        });
        _scanner = new Scanner(Console.OpenStandardInput());
        Solve();
        Console.Out.Flush();
    }
}

public static partial class Extentions
{
}

#region Library
// not tested
public class Scanner
{
    private readonly Stream _stream;
    private const int _bufferSize = 1024;
    private readonly byte[] _buf = new byte[_bufferSize];
    private int _len, _ptr;

    public Scanner(Stream stream)
    {
        _stream = stream;
    }

    public byte ReadByte()
    {
        if (_ptr >= _len) { _len = _stream.Read(_buf, 0, 1024); _ptr = 0; }
        return _buf[_ptr++];
    }

    public char ReadChar() => (char)ReadByte();

    public string ReadLine()
    {
        var r = new StringBuilder();
        if (_ptr == 0) r.Append(ReadChar());
        for (; _ptr < _len; _ptr++) r.Append((char)_buf[_ptr]);
        return r.ToString();
    }

    public char NextChar() => char.Parse(NextString());

    public string NextString()
    {
        var r = new StringBuilder();
        var b = ReadChar();
        while (b != ' ' && b != '\n') { r.Append(b); b = ReadChar(); }
        return r.ToString();
    }

    public int NextInt() => (int)NextLong();

    public long NextLong()
    {
        var r = 0L;
        var b = ReadByte();
        var n = b == '-';
        if (n) b = ReadByte();
        while (b != ' ' && b != '\n') { r = r * 10 + b - '0'; b = ReadByte(); }
        return n ? -r : r;
    }

    public BigInteger NextBigInteger()
    {
        var r = new BigInteger();
        var b = ReadByte();
        var n = b == '-';
        if (n) b = ReadByte();
        while (b != ' ' && b != '\n') { r = r * 10 + b - '0'; b = ReadByte(); }
        return n ? -r : r;
    }

    public double NextDouble()
    {
        var i = 0L;
        var b = ReadByte();
        var n = b == '-';
        if (n) b = ReadByte();
        while (b != '.') { i = i * 10 + b - '0'; b = ReadByte(); }
        var f = 0L;
        var p = 0;
        while (b != ' ' && b != '\n') { f = f * 10 + b - '0'; b = ReadByte(); p++; }
        var r = i + f / Pow(10.0, p);
        return n ? -r : r;
    }

    public decimal NextDecimal() => decimal.Parse(NextString());

    public T Next<T>(Func<string, T> parser) => parser(NextString());
}

public static partial class Extentions
{
    public static void Assert(bool condition)
    {
        if (!condition) throw new Exception();
    }

    public static string AsString(this IEnumerable<char> source) => new string(source.ToArray());

    public static void ForEach<T>(this IEnumerable<T> source, Action<T> action)
    {
        foreach (var item in source) action(item);
    }

    public static void ForEach<T, _>(this IEnumerable<T> source, Func<T, _> func)
    {
        foreach (var item in source) func(item);
    }

    public static void ForEach<T>(this IEnumerable<T> source, Action<T, int> action)
    {
        var i = 0;
        foreach (var item in source) action(item, i++);
    }

    public static void ForEach<T, _>(this IEnumerable<T> source, Func<T, int, _> func)
    {
        var i = 0;
        foreach (var item in source) func(item, i++);
    }

    public static void Repeat(int count, Action action)
    {
        for (var i = 0; i < count; i++) action();
    }

    public static void Repeat(int count, Action<int> action)
    {
        for (var i = 0; i < count; i++) action(i);
    }

    public static IEnumerable<T> Repeat<T>(Func<T> func)
    {
        for (var i = 0; ; i++) yield return func();
    }

    public static IEnumerable<T> Repeat<T>(int count, Func<T> func)
    {
        for (var i = 0; i < count; i++) yield return func();
    }

    public static IEnumerable<T> Repeat<T>(Func<int, T> func)
    {
        for (var i = 0; ; i++) yield return func(i);
    }

    public static IEnumerable<T> Repeat<T>(int count, Func<int, T> func)
    {
        for (var i = 0; i < count; i++) yield return func(i);
    }

    public static void Swap<T>(ref T x, ref T y)
    {
        var tmp = x; x = y; y = tmp;
    }
}
#endregion