[py] Port 2018_08

py/aoc/__init__.py

@@ -2,7 +2,7 @@ import sys
 import argparse
 from pathlib import Path
 
-from .y2018 import d01, d02, d03, d04, d05, d06, d07
+from .y2018 import d01, d02, d03, d04, d05, d06, d07, d08
 from .y2020 import d10
 from .y2021 import d14
 from .y2022 import d01, d02, d03, d04, d05, d06
@@ -15,6 +15,7 @@ DAYS = {
     "2018_05": y2018.d05.solve,
     "2018_06": y2018.d06.solve,
     "2018_07": y2018.d07.solve,
+    "2018_08": y2018.d08.solve,
     "2020_10": y2020.d10.solve,
     "2021_14": y2021.d14.solve,
     "2022_01": y2022.d01.solve,

py/aoc/y2018/d08.py

@@ -0,0 +1,51 @@
+# PART 1
+
+
+def load_stream(inputstr):
+    # Too lazy to do this properly
+    return list(reversed(list(map(int, inputstr[:-1].split(" ")))))
+
+
+def parse_node(stream):
+    amt_nodes = stream.pop()
+    amt_meta = stream.pop()
+
+    nodes = []
+    for _ in range(amt_nodes):
+        nodes.append(parse_node(stream))
+
+    meta = []
+    for _ in range(amt_meta):
+        meta.append(stream.pop())
+
+    return (nodes, meta)
+
+
+def sum_of_meta(node):
+    nodes, meta = node
+    return sum(meta) + sum(map(sum_of_meta, nodes))
+
+
+# PART 2
+
+
+def value_of(node):
+    nodes, meta = node
+    if nodes:
+        total = 0
+        for i in meta:
+            i -= 1
+            if i >= 0 and i < len(nodes):
+                total += value_of(nodes[i])
+        return total
+    else:
+        return sum(meta)
+
+
+def solve(inputstr):
+    stream = load_stream(inputstr)
+    node = parse_node(stream)
+    meta = sum_of_meta(node)
+    print(f"Part 1: {meta}")
+    value = value_of(node)
+    print(f"Part 2: {value}")