aoc-2021-rust

Advent of Code 2021 Solutions in Rust
git clone https://git.sinitax.com/sinitax/aoc-2021-rust
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part2 (2596B)

      1--- Part Two ---
      2
      3Now that you have the structure of your transmission decoded, you can calculate the value of the
      4expression it represents.
      5
      6Literal values (type ID 4) represent a single number as described above. The remaining type IDs are
      7more interesting:
      8
      9
     10 - Packets with type ID 0 are sum packets - their value is the sum of the values of their
     11sub-packets. If they only have a single sub-packet, their value is the value of the sub-packet.
     12
     13 - Packets with type ID 1 are product packets - their value is the result of multiplying together
     14the values of their sub-packets. If they only have a single sub-packet, their value is the value of
     15the sub-packet.
     16
     17 - Packets with type ID 2 are minimum packets - their value is the minimum of the values of their
     18sub-packets.
     19
     20 - Packets with type ID 3 are maximum packets - their value is the maximum of the values of their
     21sub-packets.
     22
     23 - Packets with type ID 5 are greater than packets - their value is 1 if the value of the first
     24sub-packet is greater than the value of the second sub-packet; otherwise, their value is
     250. These packets always have exactly two sub-packets.
     26
     27 - Packets with type ID 6 are less than packets - their value is 1 if the value of the first
     28sub-packet is less than the value of the second sub-packet; otherwise, their value is
     290. These packets always have exactly two sub-packets.
     30
     31 - Packets with type ID 7 are equal to packets - their value is 1 if the value of the first
     32sub-packet is equal to the value of the second sub-packet; otherwise, their value is 0. These
     33packets always have exactly two sub-packets.
     34
     35
     36Using these rules, you can now work out the value of the outermost packet in your BITS transmission.
     37
     38For example:
     39
     40
     41 - C200B40A82 finds the sum of 1 and 2, resulting in the value 3.
     42
     43 - 04005AC33890 finds the product of 6 and 9, resulting in the value 54.
     44
     45 - 880086C3E88112 finds the minimum of 7, 8, and 9, resulting in the value 7.
     46
     47 - CE00C43D881120 finds the maximum of 7, 8, and 9, resulting in the value 9.
     48
     49 - D8005AC2A8F0 produces 1, because 5 is less than 15.
     50
     51 - F600BC2D8F produces 0, because 5 is not greater than 15.
     52
     53 - 9C005AC2F8F0 produces 0, because 5 is not equal to 15.
     54
     55 - 9C0141080250320F1802104A08 produces 1, because 1 + 3 = 2 * 2.
     56
     57
     58What do you get if you evaluate the expression represented by your hexadecimal-encoded BITS
     59transmission?
     60
     61