day16: muuuuch nicer code

day16.py

@@ -1,100 +1,64 @@
 from math import prod
-
 from tools.aoc import AOCDay
 from typing import Any, List
 
 
-def get_packet(bit_rep: str) -> (str, int):  # packet, packet_length
+class Packet:
-    msg_type = int(bit_rep[3:6], 2)
+    def __init__(self, packet_str: str):
-    index = 6
+        self.packet_str = packet_str
+        self.p_version = int(packet_str[:3], 2)
+        self.p_type = int(packet_str[3:6], 2)
+        self.p_len = 6
+        self.value = 0
+        self.sub_packets = []
+        self.__parse()
 
-    if msg_type == 4:
+    def __parse(self):
-        while bit_rep[index] == "1":
+        if self.p_type == 4:
-            index += 5
+            while self.packet_str[self.p_len] == "1":
-        index += 5
+                self.value = self.value * 16 + int(self.packet_str[self.p_len + 1:self.p_len + 5], 2)
+                self.p_len += 5
+            self.value = self.value * 16 + int(self.packet_str[self.p_len + 1:self.p_len + 5], 2)
+            self.p_len += 5
         else:
-        op_type = bit_rep[index]
+            op_type = self.packet_str[self.p_len]
-        index += 1
+            self.p_len += 1
             if op_type == "0":
-            sub_pkg_len = int(bit_rep[index:index+15], 2)
+                sub_pkg_len = int(self.packet_str[self.p_len:self.p_len + 15], 2)
-            index += 15 + sub_pkg_len
+                self.p_len += 15 + sub_pkg_len
-        else:
+                sub_packages = self.packet_str[self.p_len - sub_pkg_len:self.p_len]
-            sub_pkg_count = int(bit_rep[index:index+11], 2)
-            index += 11
-            for x in range(sub_pkg_count):
-                _, sub_pkg_len = get_packet(bit_rep[index:])
-                index += sub_pkg_len
-
-    return bit_rep[:index], index
-
-
-def get_subpackages(packet: str) -> List[str]:
-    ptype = int(packet[3:6], 2)
-    if ptype == 4:
-        return [packet]
-    else:
-        plist = []
-        op_type = packet[6]
-        if op_type == "0":
-            sub_pkg_len = int(packet[7:22], 2)
-            sub_packages = packet[22:22+sub_pkg_len]
                 while "1" in sub_packages:
-                sub_packet, sub_pkg_len = get_packet(sub_packages)
+                    sub_packet = Packet(sub_packages)
-                sub_packages = sub_packages[sub_pkg_len:]
+                    self.sub_packets.append(sub_packet)
-                plist.append(sub_packet)
+                    sub_packages = sub_packages[sub_packet.p_len:]
             else:
-            sub_pkg_count = int(packet[7:18], 2)
+                sub_pkg_count = int(self.packet_str[self.p_len:self.p_len + 11], 2)
-            index = 18
+                self.p_len += 11
                 for x in range(sub_pkg_count):
-                sub_packet, sub_pkg_len = get_packet(packet[index:])
+                    sub_packet = Packet(self.packet_str[self.p_len:])
-                index += sub_pkg_len
+                    self.sub_packets.append(sub_packet)
-                plist.append(sub_packet)
+                    self.p_len += sub_packet.p_len
 
-        return plist
+    def get_versions(self) -> int:
+        return self.p_version + sum(p.get_versions() for p in self.sub_packets)
 
-
+    def get_value(self) -> int:
-def get_versions(packet: str) -> int:
+        if self.p_type == 0:
-    version = int(packet[0:3], 2)
+            return sum(p.get_value() for p in self.sub_packets)
-    ptype = int(packet[3:6], 2)
+        elif self.p_type == 1:
-    if ptype == 4:
+            return prod(p.get_value() for p in self.sub_packets)
-        return version
+        elif self.p_type == 2:
-    else:
+            return min(p.get_value() for p in self.sub_packets)
-        for p in get_subpackages(packet):
+        elif self.p_type == 3:
-            version += get_versions(p)
+            return max(p.get_value() for p in self.sub_packets)
-
+        elif self.p_type == 4:
-    return version
+            return self.value
-
+        elif self.p_type == 5:
-
+            return self.sub_packets[0].get_value() > self.sub_packets[1].get_value()
-def get_value(packet: str) -> int:
+        elif self.p_type == 6:
-    while "1" in packet:
+            return self.sub_packets[0].get_value() < self.sub_packets[1].get_value()
-        this_packet, pkg_len = get_packet(packet)
+        elif self.p_type == 7:
-        pkg_type = int(this_packet[3:6], 2)
+            return self.sub_packets[0].get_value() == self.sub_packets[1].get_value()
-        packet = packet[pkg_len:]
-        if pkg_type == 0:
-            return sum(get_value(p) for p in get_subpackages(this_packet))
-        elif pkg_type == 1:
-            return prod(get_value(p) for p in get_subpackages(this_packet))
-        elif pkg_type == 2:
-            return min(get_value(p) for p in get_subpackages(this_packet))
-        elif pkg_type == 3:
-            return max(get_value(p) for p in get_subpackages(this_packet))
-        elif pkg_type == 4:
-            index = 6
-            value = 0
-            while this_packet[index] == "1":
-                value = value * 16 + int(this_packet[index + 1:index + 5], 2)
-                index += 5
-            value = value * 16 + int(this_packet[index + 1:index + 5], 2)
-            return value
-        elif pkg_type == 5:
-            sub_pkg = get_subpackages(this_packet)
-            return get_value(sub_pkg[0]) > get_value(sub_pkg[1])
-        elif pkg_type == 6:
-            sub_pkg = get_subpackages(this_packet)
-            return get_value(sub_pkg[0]) < get_value(sub_pkg[1])
-        elif pkg_type == 7:
-            sub_pkg = get_subpackages(this_packet)
-            return get_value(sub_pkg[0]) == get_value(sub_pkg[1])
 
 
 class Day(AOCDay):
@@ -106,7 +70,7 @@ class Day(AOCDay):
         return "0" * (len(self.getInput()) * 4 - len(bits)) + bits
 
     def part1(self) -> Any:
-        return get_versions(self.getBits())
+        return Packet(self.getBits()).get_versions()
 
     def part2(self) -> Any:
-        return get_value(self.getBits())
+        return Packet(self.getBits()).get_value()