luaU calculator

-- developed by garfield#9172

local function add(a,b)
	if a == 0 and b == 0 then 
		return 0 
	elseif a == 0 and b == 1 then
		return 1
	elseif a == 0 and b == 2 then
		return 2
	elseif a == 0 and b == 3 then
		return 3
	elseif a == 0 and b == 4 then
		return 4
	elseif a == 0 and b == 5 then
		return 5
	elseif a == 0 and b == 6 then
		return 6
	elseif a == 0 and b == 7 then
		return 7
	elseif a == 0 and b == 8 then
		return 8
	elseif a == 0 and b == 9 then
		return 9
	elseif a == 0 and b == 10 then
		return 10
	elseif a == 0 and b == 11 then
		return 11
	elseif a == 0 and b == 12 then
		return 12
	elseif a == 0 and b == 13 then
		return 13
	elseif a == 0 and b == 14 then
		return 14
	elseif a == 0 and b == 15 then
		return 15
	elseif a == 0 and b == 16 then
		return 16
	elseif a == 0 and b == 17 then
		return 17
	elseif a == 0 and b == 18 then