View difference between Paste ID: sEhkivhG and RSgKyrXv

 -- Basic computer, chest to right, second chest below that.
 -- load top chest with witherheads and soul sand
 -- import bus on second chest will import 4 sand and 3 heads every ~3
 -- seconds, the ae update will trigger formation planes to place
 -- wither parts and construct a wither.
 -- Note: it's assumed this is at the top of a wither killing
 -- structure (using draconic grinder or equivalent)
 
 chest = peripheral.wrap("right")
 chest.condenseItems()
 
 local ok=2
 
 while ok==2 do
 ok=0
 
 for i=1,27 do
   if chest.getStackInSlot(i)~=nil and ok==0 then
     local slot = chest.getStackInSlot(i)
     print(slot.name.." is in slot "..i)
     if slot.name=="soul_sand" then
       print("Pushing soul sand down from "..i)
       chest.pushItem("down",i,4)
       ok=1
     end
 --  else
 --    print ("slot "..i.." is empty.")
   end
 end
 
 sleep(1)
 
 for i=1,27 do
   if chest.getStackInSlot(i)~=nil and ok==1 then
     local slot = chest.getStackInSlot(i)
     print(slot.name.." is in slot "..i)
     if slot.name=="skull" then
       print("Pushing skull down from "..i)
       chest.pushItem("down",i,3)
       ok=2
     end
   end
 end
 
 sleep(3)
 end