diff --git a/22/22.py b/22/22.py
index 53ec425..af40fce 100644
--- a/22/22.py
+++ b/22/22.py
@@ -1,5 +1,4 @@
 import re
-from functools import reduce
 
 
 def readInstructions(fileName):
@@ -8,54 +7,33 @@ def readInstructions(fileName):
 		lines = file.read().splitlines()
 	for line in lines:
 		result = re.search(r"x=(.+)\.\.(.+),y=(.+)\.\.(.+),z=(.+)\.\.(.+)", line).groups()
-		isOn = line.startswith("on")
-		instructions.append((isOn, tuple(int(r) for r in result)))
+		sign = 1 if line.startswith("on") else -1
+		result = tuple((sign,)) + tuple(result)
+		instructions.append(tuple(int(r) for r in result))
 	return instructions
 
 
-def contains(a, b):
-	ax1, ax2, ay1, ay2, az1, az2 = a
-	bx1, bx2, by1, by2, bz1, bz2 = b
-	return ax1 <= bx1 and ax2 >= bx2 and ay1 <= by1 and ay2 >= by2 and az1 <= bz1 and az2 >= bz2
-
-
 def volume(cube):
-	x1, x2, y1, y2, z1, z2 = cube
-	return abs(x2 - x1) * abs(y2 - y1) * abs(z2 - z1)
-
-
-def sub(a, b):
-	ax1, ax2, ay1, ay2, az1, az2 = a
-	bx1, bx2, by1, by2, bz1, bz2 = b
+	sign, x1, x2, y1, y2, z1, z2 = cube
+	return (x2 - x1 + 1) * (y2 - y1 + 1) * (z2 - z1 + 1) * sign
 
-	# if currentCube contains knownCube, remove knownCube
-	if contains(b, a):
-		return []
 
-	# if there are no intersections, do nothing
+def intersect(a, b):
+	_, ax1, ax2, ay1, ay2, az1, az2 = a
+	bSign, bx1, bx2, by1, by2, bz1, bz2 = b
 	if ax1 > bx2 or ax2 < bx1 or ay1 > by2 or ay2 < by1 or az1 > bz2 or az2 < bz1:
-		return [a]
+		return None
 
-	xSplits = filter(lambda x: ax1 < x < ax2, [bx1, bx2])
-	ySplits = filter(lambda y: ay1 < y < ay2, [by1, by2])
-	zSplits = filter(lambda z: az1 < z < az2, [bz1, bz2])
+	x1 = max(ax1, bx1)
+	x2 = min(ax2, bx2)
+	y1 = max(ay1, by1)
+	y2 = min(ay2, by2)
+	z1 = max(az1, bz1)
+	z2 = min(az2, bz2)
 
-	xValues = [ax1, *xSplits, ax2]
-	yValues = [ay1, *ySplits, ay2]
-	zValues = [az1, *zSplits, az2]
+	sign = -bSign
 
-	results = []
-	for i in range(len(xValues) - 1):
-		for j in range(len(yValues) - 1):
-			for k in range(len(zValues) - 1):
-				newC = xValues[i], yValues[j], zValues[k], xValues[i + 1], yValues[j + 1], zValues[k + 1]
-				if not contains(b, newC):
-					results.append(newC)
-	return results
-
-
-def flatMap(func, elements):
-	return [j for i in elements for j in func(i)]
+	return sign, x1, x2, y1, y2, z1, z2
 
 
 def reboot():
@@ -63,21 +41,18 @@ def reboot():
 
 	cubes = []
 
-	for turnOn, coords in instructions:
-		x1, x2, y1, y2, z1, z2 = coords
-		currentCube = x1, x2 + 1, y1, y2 + 1, z1, z2 + 1
+	for currentCube in instructions:
 
-		cubes = flatMap(lambda c: sub(c, currentCube), cubes)
+		for cube in cubes.copy():
+			if intersection := intersect(currentCube, cube):
+				cubes.append(intersection)
 
-		# add to set if 'on'
-		if turnOn:
+		if currentCube[0] == 1:
 			cubes.append(currentCube)
 
-	onCount = sum(map(volume, cubes))
-	print(onCount)
+	filteredCubes = filter(lambda c: -50 <= c[1] <= 50, cubes)
+	print(sum(map(lambda c: volume(c), filteredCubes)))
+	print(sum(map(lambda c: volume(c), cubes)))
 
 
 reboot()
-
-# on x=-54112..-39298,y=-85059..-49293,z=-27449..7877
-# on x=967..23432,y=45373..81175,z=27513..53682
\ No newline at end of file