From 9ee26756f4a9695068a68f89eccdee7b23adf2c8 Mon Sep 17 00:00:00 2001
From: Dave Pedu <dave_pedu@apple.com>
Date: Mon, 10 Dec 2018 10:15:56 -0800
Subject: [PATCH] Faster day 9

---
 9/a-dll.py | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
 9/b-dll.py | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 96 insertions(+)
 create mode 100755 9/a-dll.py
 create mode 100755 9/b-dll.py

diff --git a/9/a-dll.py b/9/a-dll.py
new file mode 100755
index 0000000..960687e
--- /dev/null
+++ b/9/a-dll.py
@@ -0,0 +1,48 @@
+#!/usr/bin/env python3
+
+
+class Node(object):
+    def __init__(self, val):
+        self.val = val
+        self.prev = None
+        self.next = None
+
+
+def main():
+    numplayers = 426
+    lastmarb = 72058
+    players = [0 for i in range(numplayers)]
+
+    currentplr = 0
+    curmarb = Node(0)
+    curmarb.next = curmarb
+    curmarb.prev = curmarb
+    nextmarb = 1
+    while True:
+        if nextmarb % 23 == 0:
+            remove = curmarb.prev.prev.prev.prev.prev.prev.prev
+            players[currentplr] += nextmarb + remove.val
+            between_a = remove.prev
+            between_b = remove.next
+            between_a.next = between_b
+            between_b.prev = between_a
+            curmarb = between_b
+        else:
+            place_between_a = curmarb.next
+            place_between_b = place_between_a.next
+            curmarb = Node(nextmarb)
+            curmarb.next = place_between_b
+            place_between_b.prev = curmarb
+            curmarb.prev = place_between_a
+            place_between_a.next = curmarb
+
+        if nextmarb == lastmarb:
+            break
+        nextmarb += 1
+        currentplr = (currentplr + 1) % numplayers
+
+    print("Winning score:", max(players))
+
+
+if __name__ == '__main__':
+    main()
diff --git a/9/b-dll.py b/9/b-dll.py
new file mode 100755
index 0000000..be846db
--- /dev/null
+++ b/9/b-dll.py
@@ -0,0 +1,48 @@
+#!/usr/bin/env python3
+
+
+class Node(object):
+    def __init__(self, val):
+        self.val = val
+        self.prev = None
+        self.next = None
+
+
+def main():
+    numplayers = 426
+    lastmarb = 72058 * 100
+    players = [0 for i in range(numplayers)]
+
+    currentplr = 0
+    curmarb = Node(0)
+    curmarb.next = curmarb
+    curmarb.prev = curmarb
+    nextmarb = 1
+    while True:
+        if nextmarb % 23 == 0:
+            remove = curmarb.prev.prev.prev.prev.prev.prev.prev
+            players[currentplr] += nextmarb + remove.val
+            between_a = remove.prev
+            between_b = remove.next
+            between_a.next = between_b
+            between_b.prev = between_a
+            curmarb = between_b
+        else:
+            place_between_a = curmarb.next
+            place_between_b = place_between_a.next
+            curmarb = Node(nextmarb)
+            curmarb.next = place_between_b
+            place_between_b.prev = curmarb
+            curmarb.prev = place_between_a
+            place_between_a.next = curmarb
+
+        if nextmarb == lastmarb:
+            break
+        nextmarb += 1
+        currentplr = (currentplr + 1) % numplayers
+
+    print("Winning score:", max(players))
+
+
+if __name__ == '__main__':
+    main()