chestexc

local args = { ... }
size = args[1]
if(size % 2 == 1) then
    size = size - 1
end

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

function move()
    if (turtle.getItemCount(16) ~= 0) then
        dropItems()
    end
    if(turtle.getFuelLevel() == 0) then
        error("Out of fuel")
    end
    while (not turtle.forward()) do
        turtle.dig()
    end
end

function right()
    turtle.turnRight()
end

function left()
    turtle.turnLeft()
end

function down3()
    for num = 1, 3 do
        turtle.digDown()
        turtle.down()
    end
end

function outer()
    for num = 1, 3 do
        for num = 2, size do
            clear()
            move()
        end
        right()
    end
end

function inner()
    peaks = (size / 2) - 1
    for num = 1, peaks do
        ascend()
        descend()
    end
    clear()
    move()
    right()
end

function ascend()
    clear()
    move()
    right()
    for num = 3, size do
        clear()
        move()
    end
    left()
end

function descend()
    clear()
    move()
    left()
    for num = 3, size do
        clear()
        move()
    end
    right()
end

function dropItems()
    right()
    right()
    turtle.select(1)
    while (not turtle.place()) do
        turtle.dig()
    end
    for num = 2, 16 do
        turtle.select(num)
        turtle.drop()
    end
    turtle.select(2)
    left()
    left()
    if(turtle.getItemCount(1) == 0) then
        error("Out of chests")
    end
end

while(true) do
    outer()
    inner()
    down3()
end