package main

import (
	"strconv"
	"strings"
	"fmt"
)

func main() {
	var x, y int
	var x1, y1 int
	fmt.Scanf("%d %d", &x, &y)
	fmt.Scanf("%d %d", &x1, &y1)
	var move = max(x, y)
	if x == y && x1 < x && x1 == y1 {
		PrintI(move + 1)
	}else {
		PrintI(move)
	}
}

func max(a int, b int) int {
	if a < b {
		return b
	}
	return a
}


func mapToString(arr []int) []string {
	ret := make([]string, len(arr))
	for i := 0; i < len(arr); i++ {
		ret[i] = strconv.Itoa(arr[i])
	}
	return ret
}

func PrintI(args ...int) {
	fmt.Println(strings.Join(mapToString(args), " "))
}