quarry

t = turtle

function f()
    if t.detect() then
        t.dig()
        t.forward()
    else
        t.forward()
    end
end
function d()
    if t.detectDown() then
        t.digDown()
        t.down()
    else
        t.down()
    end
end

function refuel()
    if t.getFuelLevel() == 0 then
            pleaseRefuel()
        end
    end
function store()
 if t.getItemCount(16) > 0 then
        pleaseStore()
    end
end

function pleaseRefuel()
    t.select(1)
    t.placeUp()
    t.suckUp()
    t.refuel()
    t.digUp()
end
function pleaseStore()
    t.select(2)
    t.digUp()
    t.placeUp()
    num = 3
    while num < 17 do
        t.select(num)
        t.dropUp()
  num = num + 1
    end
  t.select(2)
    t.digUp()
end
function checkers()
  refuel()
  store()
end

function quarry()
    x = 16
    z = 16
  dot = true
    while x > 1 do
        while z > 1 do
            checkers()
            f()
    z = z - 1
        end
  if dot then
        t.turnRight()
        f()
        t.turnRight()
  dot = not dot
   else
     t.turnLeft()
     if not (x == 2) then
     f()
     end
     t.turnLeft()
     dot = not dot
     end
   z = 16
     x = x - 1
    end
    d()
end

function downward()
  y = io.read()
  y = tonumber(y)
  while y > 0 do
    quarry()
  end
end

downward()