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

class Myon
{
    static void Main()
    {
        string[] ss;
        ss = Console.ReadLine().Split(' ');
        long x = long.Parse(ss[0]);
        long y = long.Parse(ss[1]);
        ss = Console.ReadLine().Split(' ');
        long xx = long.Parse(ss[0]);
        long yy = long.Parse(ss[1]);
        long ans;
        if(xx==yy && x==y && xx < x)
        {
            ans = x + 1;
        }
        else
        {
            ans = Math.Max(x, y);
        }
        Console.WriteLine(ans);
    }
}