From e51448bd8409893480e9cc9710385d594cc84300 Mon Sep 17 00:00:00 2001
From: Maya Herrscher <maya.herrscher@gmail.com>
Date: Sat, 17 Dec 2022 12:14:30 +0100
Subject: [PATCH] Add solution for day 16 part 2 (not necessarily correct)

---
 2022/day16/challenge |  4 ++++
 2022/day16/code.py   | 43 ++++++++++++++++++++++++++++++-------------
 2 files changed, 34 insertions(+), 13 deletions(-)

diff --git a/2022/day16/challenge b/2022/day16/challenge
index c913d63..31de3b9 100644
--- a/2022/day16/challenge
+++ b/2022/day16/challenge
@@ -227,3 +227,7 @@ Valves BB, CC, DD, EE, HH, and JJ are open, releasing 81 pressure.
 With the elephant helping, after 26 minutes, the best you could do would release a total of 1707 pressure.
 
 With you and an elephant working together for 26 minutes, what is the most pressure you could release?
+
+Your puzzle answer was 2675.
+
+Both parts of this puzzle are complete! They provide two gold stars: **
diff --git a/2022/day16/code.py b/2022/day16/code.py
index 0dadce7..388ff5c 100755
--- a/2022/day16/code.py
+++ b/2022/day16/code.py
@@ -44,7 +44,7 @@ def find_path(G,s,k):
         d = deepcopy(di)
     return max(map(max,d.values()))
 
-def Init_double(G,s,k):
+def Init2(G,s,k):
     d = {}
     o = {}
     for v in G['V']:
@@ -53,24 +53,42 @@ def Init_double(G,s,k):
     d[s] = [0] * k
     return d, o
 
-def anti_relax_double(u,v,w,i,d,k,o):
+def anti_relax2(u,v,w,i,d,k,o):
     if d[v][i] < d[u][i-1] + w[(u,v)] * (k-i):
         d[v][i] = d[u][i-1] + w[(u,v)] * (k-i)
-        o[v][i] = o[u][i-1] + [u]
+        o[v][i] = o[u][i-1] + eval(u)
 
-def find_double_path(G,s,k):
-    d,o = Init_double(G,s,k)
+def find_path2(G,s,k):
+    d,o = Init2(G,s,k)
     for i in range(k):
         di = deepcopy(d)
         for (u,v) in G['E']:
-            if d[u][i-1] > -1 and not (u[:2] == v[:2] and v in o[u][i-1]):
-                anti_relax_double(u,v,G['w'],i,di,k,o)
-        for (u,v) in G['E']:
-            if d[u][i-1] > -1 and not (u[:2] == v[:2] and (v in o[u][i-1] or v in o[u][i])):
-                anti_relax_double(u,v,G['w'],i,di,k,o)
+            u1,u2 = eval(u)
+            v1,v2 = eval(v)
+            prob = False
+            for (a,b) in [(u1,v1),(u1,v2),(u2,v1),(u2,v2)]:
+                if a[:2] == b[:2]:
+                    if a in o[u][i-1]:
+                        prob = True
+            if d[u][i-1] > -1 and not prob: anti_relax2(u,v,G['w'],i,di,k,o)
         d = deepcopy(di)
     return max(map(max,d.values()))
 
+def find_double_path(G,s,k):
+    G2 = {'V': [], 'E': [], 'w': {}}
+    for u in G['V']:
+        for v in G['V']:
+            if u == v and u[2] == 'O': continue
+            G2['V'].append(str(sorted([u,v])))
+            for e in G['E']:
+                if e[0] == u:
+                    for f in G['E']:
+                        if e[1] == f[1] and e[1][2] == 'O': continue
+                        if f[0] == v:
+                            G2['E'].append((str(sorted([u,v])),str(sorted([e[1],f[1]]))))
+                            G2['w'][(str(sorted([u,v])),str(sorted([e[1],f[1]])))] = G['w'][e] + G['w'][f]
+    return find_path2(G2,f"['{s}', '{s}']",k)
+
 
 if __name__ == '__main__':
     [parse(line.strip('\n')) for line in open(sys.argv[1])]
@@ -85,8 +103,7 @@ if __name__ == '__main__':
 
     # challenge 2
     m = find_double_path(VALVES,'AAC',25)
-    # missing: magic!
-    print(m)
-    res2 = ""
+    # missing: magic! Doesn't work for example! (off by one) But does work for input...
+    res2 = str(m)
     print("challenge 2:" + "\n" +  res2 + "\n")