tfillcli

local function detectBehind()
        turtle.turnRight()
        turtle.turnRight()
    while turtle.detect() do
        turtle.up()
        turtle.placeDown()
    end
        turtle.turnRight()
        turtle.turnRight()
end

local function goDown()
    while turtle.detectDown() == false do
        turtle.down()
    end
end

local args = {...}
    times = args[1]
        for i = 1, times do
            turtle.forward()
            goDown()
            detectBehind()
end