CC_turtle_L-tunnel

--L-tunnel
--This code will create a tunnel directly down and then in straight across in the direction it is facing, placing whatever is in slot one along the way, if it runs out of items in slot one, it moves to slot two, then slot three.. etc.
print("What's my y-coordinate boss?")
yi=read()
print("What's my goal y-coordinate boss?")
yf=read()
print("Am I facing North/South/East/West? (N/S/E/W)")
dir=read()
print("What's my coordinate in the direction I'm facing?")
xi=read()
print("What's my goal coordinate in the direction I'm facing?")
xf=read()
z=1
deltay=yi-yf
for k=1, deltay do
 t.down()
 turtle.select(z)
 turtle.placeUp()
 if turtle.getItemCount(z)==0 then
  z=z+1
 end
end
deltax=math.abs(xi-xf)
if dir=="N" or dir=="W" then
 for j=1, deltax  do
  t.forward()
  turtle.select(z)
  t.right()
  t.right()
  turtle.place()
  t.right()
  t.right()
  if turtle.getItemCount(z)==0 then
   z=z+1
  end
 end
end
deltax=math.abs(xi-xf)
if dir=="S" or dir=="E" then
 for j=1, deltax do
  t.forward()
  turtle.select(z)
  t.right()
  t.right()
  turtle.place()
  t.right()
  t.right()
  if turtle.getItemCount(z)==0 then
   z=z+1
  end
 end
end
modem.transmit(channel, 128, "Minion "..os.getComputerLabel().." has finished L-tunnel")