2024 day 5 part 2

2024/day5/day5.py

@@ -7,25 +7,39 @@ def check_update(upd, rules):
         if [a, b] not in rules:
             return False
     return True
-        
 
+def fix_update(upd, rules):
+    while not check_update(upd, rules):
+        for i in range(len(upd)):
+            for j in range(i+1, len(upd)):
+                if [upd[j], upd[i]] in rules:
+                    upd[j], upd[i] = upd[i], upd[j]
 
 def main(content):
-    order, updates = content.split("\n\n")
-    order = [x.split("|") for x in order.split("\n")]
+    rules, updates = content.split("\n\n")
+    rules = [x.split("|") for x in rules.split("\n")]
     updates = [x.split(",") for x in updates.rstrip().split("\n")]
 
     part1 = 0
+    incorrect_updates = []
     for update in updates:
-        if check_update(update, order):
+        if check_update(update, rules):
             middle = update[len(update)//2]
             part1 += int(middle)
+        else:
+            incorrect_updates.append(update)
     print("Part 1: ", part1)
 
+    part2 = 0
+    for update in incorrect_updates:
+        fix_update(update, rules)
+        middle = update[len(update)//2]
+        part2 += int(middle)
+    print("Part 2: ", part2)
+
 
 if __name__ == "__main__":
     import sys
     infile = sys.argv[1] if 1 < len(sys.argv) else "example.txt"
     with open(infile) as f:
         main(f.read())
-