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

namespace yukicoderTest
{
    class Program
    {
        static void Main(string[] args)
        {
            string input = Console.ReadLine();
            string input2 = Console.ReadLine();
            string holiday = input + input2;
            int cnt = 0;
            int total = 0;
            for (int i = 0; i < holiday.Length - 1; i++)
            {
                string temp = holiday.Substring(i, 1);
                cnt = 0;
                bool flg = false;
                for (int j = i+1; j < holiday.Length; j++)
                {
                    string tmp = holiday.Substring(j, 1);
                    if (temp == "o" && tmp == "o" && flg == false) 
                    {
                        cnt+=2;
                        flg = true;
                    }
                    else if(temp == "o" && tmp == "o" && flg == true)
                    {
                        cnt++;
                    }
                    else
                    {
                        flg = false;
                        break;
                    }
                }
                if (total < cnt)
                {
                    total = cnt;
                }
            }
            Console.WriteLine(total);
        }

    }
}