day04 finished

advent/days/day04/solution.py

@@ -0,0 +1,55 @@
+from __future__ import annotations
+from dataclasses import dataclass
+
+from typing import Iterator
+
+day_num = 4
+
+
+def part1(lines: Iterator[str]) -> int:
+    return sum(1 for line in lines if Pair.parse(line).includes())
+
+
+def part2(lines: Iterator[str]) -> int:
+    return sum(1 for line in lines if Pair.parse(line).overlap())
+
+
+@dataclass(slots=True, frozen=True)
+class Range:
+    start: int
+    end: int
+
+    @staticmethod
+    def parse(line: str) -> Range:
+        match line.split('-'):
+            case [s, e]: return Range(int(s), int(e))
+            case _: raise Exception(f"Not a valid range: {line}")
+
+    def includes(self, other: Range) -> bool:
+        """ Check if this range includes the other """
+        return self.start <= other.start and self.end >= other.end
+
+    def overlap(self, other: Range) -> bool:
+        """ Check if this range obverlaps with the other """
+        return (self.start >= other.start and self.start <= other.end) or (
+            other.start >= self.start and other.start <= self.end)
+
+
+@dataclass(slots=True, frozen=True)
+class Pair:
+    first: Range
+    second: Range
+
+    @staticmethod
+    def parse(line: str) -> Pair:
+        match line.split(','):
+            case [f, s]: return Pair(Range.parse(f), Range.parse(s))
+            case _: raise Exception(f"Not a valid Pair: {line}")
+
+    def includes(self) -> bool:
+        """ Check if one range includes the other """
+        return self.first.includes(self.second) or self.second.includes(self.first)
+
+    def overlap(self) -> bool:
+        """ Check if the two ranges obverlap """
+        return self.first.overlap(self.second)