using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.Text;
using System.Text.RegularExpressions;
using System.Linq;

class Magatro
{
    static void Main()
    {
        string[] s = Console.ReadLine().Split(' ');
        string[] ss = Console.ReadLine().Split(' ');
       
        int max = Math.Max(int.Parse(s[0]), int.Parse(s[1]));
        if (s[0] == s[1] && ss[0] == ss[1])
        {
            max++;
        }
        Console.WriteLine(max);
    }
  
}