import scala.io.StdIn.readLine
import scala.collection.mutable.PriorityQueue
import scala.annotation.tailrec

// PriorityQueue[Long]()(scala.math.Ordering.Long.reverse)
package net.pushl {
  package number {
    // Prime  (Prime.scala)
    // Number (Number.scala)
  }
  package string {
    // RollingHash (RollingHash.scala)
  }
  package geometry {
    // Point
    // Segment
    // Line
  }
  object EnRich {
    implicit class AString(val self : String) extends AnyVal {
      def splitToIntVector    = self.split(" ").map(_.toInt).toVector
      def splitToDoubleVector = self.split(" ").map(_.toDouble).toVector

      def splitToDoubleTuple2 = splitTuple2(() => splitToDoubleVector)
      def splitToIntTuple2    = splitTuple2(() => splitToIntVector)
      def splitToDoubleTuple3 = splitTuple3(() => splitToDoubleVector)
      def splitToIntTuple3    = splitTuple3(() => splitToIntVector)

      private def splitTuple2[X](splitTo: () => Vector[X]) = {
        val ab = splitTo()
        (ab(0),ab(1))
      }
      private def splitTuple3[X](splitTo: () => Vector[X]) = {
        val abc = splitTo()
        (abc(0),abc(1),abc(2))
      }
    }
  }
}

import net.pushl.EnRich._
object Main {
  def main(args : Array[String]) : Unit = {
    val (x,y)   = readLine.splitToIntTuple2
    val (x2,y2) = readLine.splitToIntTuple2
    if(x == y && x2 == y2 && x2 < x)
      println(x+1)
    else
      println(x max y)
  }
}