Mining program created with Blockly Lua

function explore()
  for count = 1, 4 do
    if turtle.detect() and interesting_block_ahead() then
      while turtle.detect() do
        if not turtle.dig() then
          return
        end
        sleep(0.8)
      end
      if turtle.forward() then
        explore()
        turtle.back()
      end
    end
    turtle.turnRight()
  end
end

function mine(max_depth)
  depth = 0
  for count2 = 1, math.floor(max_depth) do
    if turtle.detectDown() and not turtle.digDown() then
      break
    end
    depth = depth + 1
    turtle.down()
    explore()
  end
  for count3 = 1, math.floor(depth) do
    turtle.up()
  end
end

function interesting_block_ahead()
  for _, k in ipairs(boring_slots) do
    turtle.select(k)
    if turtle.compare() then
      return false
    end
  end
  return true
end


boring_slots = ({12, 13, 14, 15, 16})

mine(10)