Do part 2 using the slice algorithm.

day-06/part2.py

@@ -1,42 +0,0 @@
-from __future__ import print_function
-import fileinput
-import re
-import sys
-
-commandExpr = re.compile(r"^(toggle|turn (on|off)) (\d+),(\d+) through (\d+),(\d+)$")
-
-lights = []
-for x in range(1000):
-    lights.append([])
-    for y in range(1000):
-        lights[x].append(0)
-
-for line in fileinput.input():
-    match = commandExpr.search(line)
-
-    if not match:
-        print("Invalid string")
-        sys.exit(1)
-
-    xStart = int(match.group(3))
-    yStart = int(match.group(4))
-
-    xEnd = int(match.group(5))
-    yEnd = int(match.group(6))
-
-    command = match.group(1)
-
-    for x in range(xStart, xEnd + 1):
-        for y in range(yStart, yEnd + 1):
-            if command == "toggle":
-                lights[x][y] += 2
-            elif "on" in command:
-                lights[x][y] += 1
-            else:
-                lights[x][y] = max(0, lights[x][y] - 1)
-
-total = 0
-for row in lights:
-    total += sum(row)
-
-print(total)

day-06/solution.py

@@ -23,7 +23,7 @@ def compact(lightList):
 
 def updateState(sliceList, yStart, yEnd, updateFnc):
     newList = []
-    for start, end, state in lights[x]:
+    for start, end, state in sliceList:
         if not start <= yStart  <= end and not yStart <= start <= yEnd:
             # Block not in range, skip
             newList.append((start, end, state))
@@ -54,9 +54,19 @@ def getPart1Update(command):
     else:
         return lambda _: False
 
-lights = []
+def getPart2Update(command):
+    if "toggle" in command:
+        return lambda x: x + 2
+    elif "on" in command:
+        return lambda x: x + 1
+    else:
+        return lambda x: max(0, x - 1)
+
+lights1 = []
+lights2 = []
 for x in range(1000):
-    lights.append([(0, 999, False)])
+    lights1.append([(0, 999, False)])
+    lights2.append([(0, 999, 0)])
 
 for line in fileinput.input():
     match = re.search(r"^(toggle|turn (on|off)) (\d+),(\d+) through (\d+),(\d+)$", line)
@@ -70,8 +80,8 @@ for line in fileinput.input():
     command = match.group(1)
 
     for x in range(xStart, xEnd + 1):
-        lights[x] = updateState(lights[x], yStart, yEnd, getPart1Update(command))
+        lights1[x] = updateState(lights1[x], yStart, yEnd, getPart1Update(command))
+        lights2[x] = updateState(lights2[x], yStart, yEnd, getPart2Update(command))
 
-total = sum(colsum(x) for x in lights)
+print("Lights on:", sum(colsum(x) for x in lights1))
-
+print("Lumen:", sum(colsum(x) for x in lights2))
-print(total)