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--- Part Two ---
As you look over the list of messages, you realize your matching rules aren't quite right. To fix
them, completely replace rules 8: 42 and 11: 42 31 with the following:
8: 42 | 42 8
11: 42 31 | 42 11 31
This small change has a big impact: now, the rules [1m[37mdo[0m contain loops, and the list of
messages they could hypothetically match is infinite. You'll need to determine how these changes
affect which messages are valid.
Fortunately, many of the rules are unaffected by this change; it might help to start by looking at
which rules always match the same set of values and how [1m[37mthose[0m rules (especially rules
42 and 31) are used by the new versions of rules 8 and 11.
(Remember, [1m[37myou only need to handle the rules you have[0m; building a solution that could
handle any hypothetical combination of rules would be significantly more difficult.)
For example:
42: 9 14 | 10 1
9: 14 27 | 1 26
10: 23 14 | 28 1
1: "a"
11: 42 31
5: 1 14 | 15 1
19: 14 1 | 14 14
12: 24 14 | 19 1
16: 15 1 | 14 14
31: 14 17 | 1 13
6: 14 14 | 1 14
2: 1 24 | 14 4
0: 8 11
13: 14 3 | 1 12
15: 1 | 14
17: 14 2 | 1 7
23: 25 1 | 22 14
28: 16 1
4: 1 1
20: 14 14 | 1 15
3: 5 14 | 16 1
27: 1 6 | 14 18
14: "b"
21: 14 1 | 1 14
25: 1 1 | 1 14
22: 14 14
8: 42
26: 14 22 | 1 20
18: 15 15
7: 14 5 | 1 21
24: 14 1
abbbbbabbbaaaababbaabbbbabababbbabbbbbbabaaaa
bbabbbbaabaabba
babbbbaabbbbbabbbbbbaabaaabaaa
aaabbbbbbaaaabaababaabababbabaaabbababababaaa
bbbbbbbaaaabbbbaaabbabaaa
bbbababbbbaaaaaaaabbababaaababaabab
ababaaaaaabaaab
ababaaaaabbbaba
baabbaaaabbaaaababbaababb
abbbbabbbbaaaababbbbbbaaaababb
aaaaabbaabaaaaababaa
aaaabbaaaabbaaa
aaaabbaabbaaaaaaabbbabbbaaabbaabaaa
babaaabbbaaabaababbaabababaaab
aabbbbbaabbbaaaaaabbbbbababaaaaabbaaabba
Without updating rules 8 and 11, these rules only match three messages: bbabbbbaabaabba,
ababaaaaaabaaab, and ababaaaaabbbaba.
However, after updating rules 8 and 11, a total of [1m[37m12[0m messages match:
- bbabbbbaabaabba
- babbbbaabbbbbabbbbbbaabaaabaaa
- aaabbbbbbaaaabaababaabababbabaaabbababababaaa
- bbbbbbbaaaabbbbaaabbabaaa
- bbbababbbbaaaaaaaabbababaaababaabab
- ababaaaaaabaaab
- ababaaaaabbbaba
- baabbaaaabbaaaababbaababb
- abbbbabbbbaaaababbbbbbaaaababb
- aaaaabbaabaaaaababaa
- aaaabbaabbaaaaaaabbbabbbaaabbaabaaa
- aabbbbbaabbbaaaaaabbbbbababaaaaabbaaabba
[1m[37mAfter updating rules 8 and 11, how many messages completely match rule 0?[0m
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