using System;

public class Program

{

    public static void Main()

    {

        string[] arr=new string[1]{"110011"};

        int count=0;

        int res=0;

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

        {

            arr[i]=Console.ReadLine();

        }

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

        {

            if(Convert.ToInt32(arr[i]) ==0)

            {

                count=0;

            }

            else

                {

                    res++;

                    res=count>res?count:res;

                }

        }

        Console.WriteLine(res);

        //Console.WriteLine("Hello World");

    }

}