gistfile1

# assumes:
# X >= Y >= Z  (will work otherwise, but suboptimally)

turn_switch = False

def switch():
    if turn_switch:
	turn_switch = False
    else:
	turn_switch = True

def dig_line():
    for i in range(x):  # Do z times
	dig
	move forward

def dig_layer():
    for i in range(y):
	dig_line()
	if turn_switch:
	    turn left
	    move forward
	    turn left
	    switch()
	else:
	    turn right
	    move forward
	    turn right
	    switch()

def dig_rectangle():
    for i in range(z):
	dig_layer()
	move down
	turn right
	turn right
	switch()