for _,dim in pairs({"width","length","height"}) do
	while not _G[dim] do
		io.write("Enter "..dim..": ")
		_G[dim] = tonumber(io.read())
		if not _G[dim] then print("Invalid entry") end
	end
end
area=(2*width+2*length)*height
print(string.format("Total size: %d, Gallons needed: %d, Leftover: %f",area,math.ceil(area/150),1-area/150%1))