import std.algorithm, std.array, std.container, std.range, std.bitmanip;
import std.numeric, std.math, std.bigint, std.random, core.bitop;
import std.string, std.regex, std.conv, std.stdio, std.typecons;

void main()
{
  auto rd1 = readln.split.map!(to!int);
  auto x = rd1[0], y = rd1[1];
  auto rd2 = readln.split.map!(to!int);
  auto x2 = rd2[0], y2 = rd2[1];

  auto r = min(x, y);
  r += (x - r) + (y - r);
  if (x == y && x2 == y2 && x > x2) r += 1;
  writeln(r);
}