More fence layin

local selection = 1
local z = 1
turtle.select(1)

local function restock()
        turtle.select(16)
        turtle.place()

        for i=1,15 do
                turtle.select(i)
                turtle.suck()

        turtle.select(16)
        turtle.dig()
        turtle.select(1)
end

local function placeFence()
        turtle.digDown()
        turtle.placeDown()
    while not turtle.forward() do
                turtle.dig()
        end
    while turtle.getItemCount(selection) == 0 do
                selection = selection + 1
                turtle.select(selection)
        end


    if selection == 16 then
        restock()
        selection = 1
    end
    turtle.select(selection)
end

local function howBig()
    term.clear()
    term.setCursorPos(1,1)
    print("How long do you want the quarry?")
    x = tonumber(read())
    print("How wide do you want the quarry?")
    y = tonumber(read())
    print("Laying fence "..x.." by "..y)
end

local function layinFence()
    for i=1,x-1 do
        placeFence()
    end
    turtle.turnLeft()
    for i=1,y-1 do
        placeFence()
    end
    turtle.turnLeft()
    for i=1, x-1 do
        placeFence()
    end
    turtle.turnLeft()
    for i=1, y-1 do
        placeFence()
    end
    turtle.turnLeft()
end

howBig()
layinFence()