replace

local arg = {...}

local x = arg[1]
local y = arg[2]

local select = 1

function isEnough()
    if turtle.getItemCount( turtle.getSelectedSlot()) < 1 then
                select = select + 1
                if select > 16 then
                    select = 1
        end
    end
end

function place()
    if turtle.detectDown() then
            turtle.digDown()
 turtle.placeDown()
            else
    turtle.placeDown()
        end
end

turtle.turnRight()
place()

for j = 0, (y-1) do
    for i = 0, (x-2) do
        turtle.forward()
        place()
    end
    if j%2 ~= 0 then
        turtle.turnRight()
        turtle.forward()
        place()
        turtle.turnRight()
            else
        turtle.turnLeft()
        turtle.forward()
        place()
        turtle.turnLeft()
    end
end