import strutils, sequtils

proc getInts: tuple[x, y: int] =
  let t = stdin.readLine.split.map parseInt
  result = (t[0], t[1])

let
  (x, y) = getInts()
  (x2, y2) = getInts()
var
  offset = 0

if x == y and x2 == y2 and x > x2:
  offset += 1

echo max(x, y) + offset