diff --git a/2022/day18.py b/2022/day18.py
index 090be07..50a4606 100644
--- a/2022/day18.py
+++ b/2022/day18.py
@@ -18,33 +18,16 @@ sample_coords = [tuple(line_to_numbers(line)) for line in '''
 2,3,5
 '''.strip().split('\n')]
 
-def count_faces(coords: list[tuple[int,int,int]]):
-	# print(coords)
-	surface_area = 0
-	for (x,y,z) in coords:
-		if (x+1,y,z) not in coords:
-			surface_area += 1
-		if (x-1,y,z) not in coords:
-			surface_area += 1
-		if (x,y+1,z) not in coords:
-			surface_area += 1
-		if (x,y-1,z) not in coords:
-			surface_area += 1
-		if (x,y,z+1) not in coords:
-			surface_area += 1
-		if (x,y,z-1) not in coords:
-			surface_area += 1
-	return surface_area
-
-print(f'Part 1 (sample): {count_faces(sample_coords)}')
-print(f'Part 1: {count_faces(coords)}')
-
-def count_faces_2(coords: list[tuple[int,int,int]]):
+def count_faces(coords: list[tuple[int,int,int]], count_gaps=True):
 	# we pad to ensure the outer edges are fine
-	field = np.zeros((25,25,25), dtype=np.int8)
+	field = np.full((25,25,25), -1 if count_gaps else 0, dtype=np.int8)
+	# indices = np.array(coords, dtype=np.int8).T + 1
+	# field[*indices] = 1
 	for (x,y,z) in coords:
 		field[x+1,y+1,z+1] = 1
-	field[flood(field, (0,0,0), connectivity=1)] = -1
+
+	if not count_gaps:
+		field[flood(field, (0,0,0), connectivity=1)] = -1
 
 	surface_area  = np.logical_and(field[:-1,:,:] == 1, field[1:,:,:] == -1).sum()
 	surface_area += np.logical_and(field[1:,:,:] == 1, field[:-1,:,:] == -1).sum()
@@ -54,6 +37,22 @@ def count_faces_2(coords: list[tuple[int,int,int]]):
 	surface_area += np.logical_and(field[:,:,1:] == 1, field[:,:,:-1] == -1).sum()
 	return surface_area
 
+print(f'Part 1 (sample): {count_faces(sample_coords)}')
+print(f'Part 1: {count_faces(coords)}')
 
-print(f'Part 2 (sample): {count_faces_2(sample_coords)}')
-print(f'Part 2: {count_faces_2(coords)}')
+
+print(f'Part 2 (sample): {count_faces(sample_coords, False)}')
+t0 = perf_counter_ns()
+print(f'Part 2: {count_faces(coords, False)}')
+t1 = perf_counter_ns()
+
+for i in range(1000):
+	count_faces(coords, False)
+t2 = perf_counter_ns()
+for i in range(10000):
+	count_faces(coords, False)
+t3 = perf_counter_ns()
+
+print(f'Part 2 x1: {(t1-t0)/1000_000:.3f}ms')
+print(f'Part 2 x1000: {(t2-t1)/1000_000:.3f}ms')
+print(f'Part 2 x10000: {(t3-t2)/1000_000:.3f}ms')