func main()
	var n: int :: cui@inputInt()
	var a: [][]char :: cui@input().split(" ")
	var b: [][]char :: cui@input().split(" ")
	do a.sort()
	do b.sort()
	for i(0, n - 2)
		if(a[i] <> b[i])
			do cui@print("\{a[i]}\n")
			ret
		end if
	end for
	do cui@print("\{a[n - 1]}\n")
end func