retyped day2, completed days 3 and 4, modified template

day4/common.py

@@ -0,0 +1,29 @@
+from __future__ import annotations
+
+import re
+from typing import NamedTuple
+
+
+class Range(NamedTuple):
+    first: int
+    last: int
+
+    def __contains__(self, other: Range) -> bool:
+        return self.first <= other.first and self.last >= other.last
+
+    def __str__(self):
+        return f"{self.first}-{self.last}"
+
+    def overlaps_with(self, other: Range) -> bool:
+        return Range(other.first, other.first) in self or Range(other.last, other.last) in self
+
+
+def parse(filename: str) -> list[tuple[Range, Range]]:
+    pairs = []
+    with open(filename) as f:
+        while line := f.readline():
+            if match := re.match(r"(\d+)-(\d+),(\d+)-(\d+)", line):
+                pairs.append(
+                    (Range(int(match.group(1)), int(match.group(2))), Range(int(match.group(3)), int(match.group(4))))
+                )
+    return pairs