using System;
using System.Collections.Generic;

internal class MainClass
{
    public static void Main(string[] args)
    {
        string st = Console.ReadLine();
        List<int> list = new List<int>();
        int count = 0;

        for (int i = 0; i < st.Length / 2; i++)
        {
            Console.WriteLine(st[1]);
            if (st[i] == st.Length - i)
            {
                count += 1;
            }
        }
        Console.WriteLine(count);
        Console.ReadKey();
    }
}