Decompress Slabs

-- Assume that spots 5-16 are empty (wouldn't need slabs to constructing bridge)
-- 1-4 are: Chest, Coal, Triple Compressed Cobblestone, Double Compressed Cobblestone

-- place chest above for inventory, chest below for stacks
turtle.select(1) turtle.digUp() turtle.digDown()

-- use a crafty mining/digging turtle to avoid this
if not turtle.placeUp() or not turtle.placeDown() then os.shutdown() end

-- leave only double compressed in inventory.
-- if 3 or less double compressed, make 54 new double compressed
turtle.select(1) if turtle.getItemCount(4) < 4 then turtle.dropUp() turtle.select(2) turtle.dropUp() turtle.select(4) turtle.dropUp() turtle.craft(6) turtle.select(3) turtle.dropUp() else for i=1,3 do turtle.select(i) turtle.dropUp() end end

-- make 18 compressed, deposit double compressed
turtle.select(5) turtle.craft(2) turtle.select(4) turtle.dropUp()

-- decompress into 3 stacks
turtle.select(6) turtle.craft(6) turtle.dropDown() turtle.craft(6) turtle.dropDown() turtle.craft(9)

-- suck up two stacks of cobblestone, balance stacks
turtle.select(5) turtle.suckDown() turtle.select(7) turtle.suckDown() turtle.select(5) turtle.transferTo(7, 10) turtle.select(8)

-- should have 3 stacks of 54 cobblestone. 6 slabs per craft means we can craft at most 10 at a time. Rounding up 54/10 gives us 6 iterations.
for i=1,5 do turtle.craft(10) turtle.dropDown() end turtle.craft(10)

-- starting at index 1, get all of our stuff back
turtle.select(1) while turtle.suckUp() do end while turtle.suckDown() do end

-- get our chests back
turtle.digUp() turtle.digDown()