using System;
using System.Text;
using System.Linq;

namespace ConsoleApp11
{
    class Program
    {
        static void Main(string[] args)
        {
            int count = 0;
            int max = 0;

            char[,] C = new char[2,7];

            for(int i = 0; i < 2; i++)
            {
                var input = Console.ReadLine().Trim();

                for(int j = 0; j < 7; j++)
                {
                    C[i, j] = input[j];
                }
            }

            for(int i = 0; i < 2; i++)
            {
                for(int j = 0; j < 7; j++)
                {
                    if (C[i, j] == 'o')
                    {
                        count++;

                        if (count > max)
                        {
                            max = count;
                        }
                    }
                    else if (C[i, j] == 'x')
                    {
                        count = 0;
                    }
                }
            }
            Console.WriteLine(max);
        }        
    }
}