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

namespace Електронно_съобщение
{
    class Program
    {
        static void Main(string[] args)
        {
            string a = Console.ReadLine();
            char[] b = a.ToLower().ToCharArray();



            int count = 0;
            int countMax = 0;

            for (int i = 0; i < b.Length; i++)
            {


                char z = b[i];



                if (
                    z == 'a' || z == 'b' || z == 'c' || z == 'd' || z == 'e' || z == 'f' || z == 'g' || z == 'h' || z == 'i'
                    || z == 'j' || z == 'k' || z == 'l' || z == 'm' || z == 'n' || z == 'o' || z == 'p' || z == 'r' || z == 'q' ||
                    z == 's' || z == 't' || z == 'u' || z == 'v' || z == 'w' || z == 'x' || z == 'y' || z == 'Z' || z == '0'
                    || z == '1' || z == '2' || z == '3' || z == '4' || z == '5' || z == '6' || z == '7' || z == '8' || z == '9' || z == '.' || z == ' ' ||
                    z == null)
                {
                    count = 0;
                }

                if (
                z != 'a' && z != 'b' && z != 'c' && z != 'd' && z != 'e' && z != 'f' && z != 'g' && z != 'h' && z != 'i'
                && z != 'j' && z != 'k' && z != 'l' && z != 'm' && z != 'n' && z != 'o' && z != 'p' && z != 'r' && z != 'q' &&
                z != 's' && z != 't' && z != 'u' && z != 'v' && z != 'w' && z != 'x' && z != 'y' && z != 'Z' && z != '0'
                && z != '1' && z != '2' && z != '3' && z != '4' && z != '5' && z != '6' && z != '7' && z != '8' && z != '9' && z != '.' && z != ' ')
                {
                    count++;
                }


                if (countMax <= count)
                {
                    countMax = count;
                }


            }
            Console.WriteLine(countMax);

        }
    }
}