[py] Port 2016_03

py/aoc/__init__.py

@@ -2,7 +2,7 @@ import sys
 import argparse
 from pathlib import Path
 
-from .y2016 import d01, d02
+from .y2016 import d01, d02, d03
 from .y2017 import d01, d02, d03, d04, d05, d06, d07, d08, d09
 from .y2018 import d01, d02, d03, d04, d05, d06, d07, d08, d09, d10, d11
 from .y2020 import d10
@@ -12,6 +12,7 @@ from .y2022 import d01, d02, d03, d04, d05, d06
 DAYS = {
     "2016_01": y2016.d01.solve,
     "2016_02": y2016.d02.solve,
+    "2016_03": y2016.d03.solve,
     "2017_01": y2017.d01.solve,
     "2017_02": y2017.d02.solve,
     "2017_03": y2017.d03.solve,

py/aoc/y2016/d03.py

@@ -0,0 +1,45 @@
+import re
+
+TRIANGLE_RE = r"\s*(\d+)\s+(\d+)\s+(\d+)"
+
+
+def load_triangles(inputstr):
+    triangles = []
+    for line in inputstr.splitlines():
+        match = re.fullmatch(TRIANGLE_RE, line)
+        a, b, c = match.groups()
+        a, b, c = int(a), int(b), int(c)
+        triangles.append((a, b, c))
+    return triangles
+
+
+# PART 1
+
+
+def is_valid(triangle):
+    a, b, c = sorted(triangle)
+    return a + b > c
+
+
+def count_valid(triangles):
+    return len(list(filter(is_valid, triangles)))
+
+
+# PART 2
+
+
+def transform_triangles(triangles):
+    new_triangles = []
+    while triangles:
+        t1, t2, t3 = triangles[:3]
+        triangles = triangles[3:]
+        new_triangles.extend(zip(t1, t2, t3))
+    return new_triangles
+
+
+def solve(inputstr):
+    triangles = load_triangles(inputstr)
+    valid = count_valid(triangles)
+    print(f"Part 1: {valid}")
+    valid_2 = count_valid(transform_triangles(triangles))
+    print(f"Part 2: {valid_2}")