local function clear()
    turtle.digUp()
    turtle.digDown()
    turtle.dig()
end

local function clearLine(n)
    for _ = 1, n do
        clear()
        if not turtle.forward() then
            return false
        end
    end
    return true
end

local function clearArea(f, l)
    if not clearLine(f - 1) then
        return false
    end

    turtle.turnLeft()

    if not clearLine(l - 1) then
        return false
    end

    turtle.turnLeft()

    if not clearLine(f - 1) then
        return false
    end

    local repeats = math.floor(l / 2) - 1

    for _ = 1, repeats do
        turtle.turnLeft()
        clear()
        if not turtle.forward() then
            return false
        end
        turtle.turnLeft()
        if not clearLine(f - 2) then
            return false
        end
        turtle.turnRight()
        clear()
        if not turtle.forward() then
            return false
        end
        turtle.turnRight()
        if not clearLine(f - 2) then
            return false
        end
    end
end

local args = { ... }
local f = args[1] or 0
local l = args[2] or 0

local fl = turtle.getFuelLevel()
if fl >= f * l then
    clearArea(f, l)
else
    print 'not enougth of fueld'
end