func main()
	var a: int :: cui@inputInt()
	var b: int :: cui@inputInt()
	var c: int :: cui@inputInt()
	var ans: int :: 0
	if(a = b & b = c)
		do ans :: a
	elif(a <> b & b <> c & c <> a)
		do ans :: 6 - a - b - c
	else
		if(a = b)
			do ans :: c
		elif(b = c)
			do ans :: a
		else
			do ans :: b
		end if
	end if
	do cui@print("\{ans}\n")
end func