add remaining code and input files from 2020

AoC2020/code/AoC19.py

@@ -1,44 +1,60 @@
-#!/usr/bin/env python3
-
-import sys
 import re
 
-def parse_rules(lines):
-    rules =  {}
-    for line in lines:
-        rule, pattern = line.split(':')
-        alternatives = pattern.split('|')
-        rules[int(rule)] = [a.strip(' ').split(' ') for a in alternatives]
-    return rules
 
 def memo(f):
-   mem = {}
-   def helper(x):
-      if x not in mem: mem[x] = f(x)
-      return mem[x]
-   return helper
+    memo = {}
+
+    def f2(x):
+        if x not in memo:
+            memo[x] = f(x)
+        return memo[x]
+
+    return f2
+
+
+def parse(l):
+    srules = re.compile(r"(?P<rule>\d+): (?P<num1>\d+)\n").findall(l)
+    rules = re.compile(r"(?P<rule>\d+): (?P<num1>\d+) (?P<num2>\d+)\n").findall(l)
+    wrules = re.compile(r"(?P<rule>\d+): \"(?P<body>\w)\"\n").findall(l)
+    crules = re.compile(r"(?P<rule>\d+): (?P<num11>\d+) (?P<num12>\d+) \| (?P<num21>\d+) (?P<num22>\d+)\n").findall(l)
+    csrules = re.compile(r"(?P<rule>\d+): (?P<num11>\d+) \| (?P<num21>\d+)\n").findall(l)
+    messages = re.compile(r"(?P<message>\w+)\n").findall(l)
+    return rules, wrules, crules, srules, csrules, messages
+
+
+def check_if_valid(message):
+    return 0
+
 
 @memo
-def expr(rule):
-    if rule == 8:
-        return expr(42) + '+'
-    if rule == 11:
-        return '(?:' + expr(42) + '(?=a*(\1?+b)b*(\2?+c)))+\1' + expr(31) + ')'
-    global rules
-    if type(rule) is str: 
-        try: rule = int(rule)
-        except ValueError: return rule[1]
-    pattern = rules[rule]
-    res = ["".join(expr(dep) for dep in alt) for alt in pattern]
-    if len(res) == 1: return res[0]
-    return "(" + "|".join(res) + ")"
+def build_regex(rule):
+    if dict[rule] == 'a' or dict[rule] == 'b':
+        return dict[rule]
+    if type(dict[rule]) == int:
+        return build_regex(dict[rule])
+    s = "("
+    for i, r in enumerate(dict[rule]):
+        if i == 2:
+            s += ")|("
+        s += build_regex(r)
+    return s + ")"
 
-if __name__ == '__main__':
-    rules, messages = open(sys.argv[1]).read().split('\n\n')
-    rules = parse_rules(rules.split('\n'))
-    count = 0
-    messages = messages.split("\n")
-    for m in messages: 
-        if bool(re.match('^' + expr(0) + '$', m)):
-            count += 1
-    print(count)
+
+with open(r"C:\Users\Maya\Desktop\Uni\WS_2021\AoC\input19") as f:
+    lines = f.readlines()
+    lines = "".join(lines)
+    r, w, c, s, messages = parse(lines)
+    rules = r + w + c + s
+    dict = {}
+    for rule in rules:
+        if len(rule) == 2:
+            try: dict[int(rule[0])] = int(rule[1])
+            except ValueError: dict[int(rule[0])] = rule[1]
+        if len(rule) == 3:
+            dict[int(rule[0])] = int(rule[1]), int(rule[2])
+        if len(rule) == 5:
+            dict[int(rule[0])] = int(rule[1]), int(rule[2]), int(rule[3]), int(rule[4])
+
+    print(dict)
+    print(build_regex(0))
+    print(sum([check_if_valid(m) for m in messages]))