From 0b715584879ddea7d72a6b033faf8fa43595aa2e Mon Sep 17 00:00:00 2001
From: Tomasz Kramkowski <tomasz@kramkow.ski>
Date: Mon, 11 Dec 2023 15:17:00 +0000
Subject: day 11 more functional

---
 11.py | 52 +++++++++++++++++++++++++++++++---------------------
 1 file changed, 31 insertions(+), 21 deletions(-)

diff --git a/11.py b/11.py
index 645c6c7..ae1b6a8 100644
--- a/11.py
+++ b/11.py
@@ -1,38 +1,48 @@
 # pyright: strict
-from itertools import accumulate, combinations
+from collections.abc import Callable, Iterable, Iterator
+from dataclasses import dataclass
+from itertools import accumulate, combinations, starmap
 from sys import stdin
+from typing import Self
+
+
+@dataclass(frozen=True, slots=True)
+class Point:
+    x: int
+    y: int
+
+    def distance(self, other: Self) -> int:
+        return abs(self.x - other.x) + abs(self.y - other.y)
+
+    def __add__(self, other: Self) -> Self:
+        return self.__class__(self.x + other.x, self.y + other.y)
 
 
 def offsets(length: int, present: set[int]) -> list[int]:
     return list(accumulate(1 if i not in present else 0 for i in range(length)))
 
 
-def solve(
-    points: set[tuple[int, int]],
-    x_offsets: list[int],
-    y_offsets: list[int],
-    expansion: int = 2,
-) -> int:
-    def offset(p: tuple[int, int]) -> tuple[int, int]:
-        return (
-            p[0] + x_offsets[p[0]] * (expansion - 1),
-            p[1] + y_offsets[p[1]] * (expansion - 1),
-        )
+def dists(points: Iterable[Point]) -> Iterator[int]:
+    return starmap(Point.distance, combinations(points, 2))
+
+
+def offsetter(
+    x_offsets: list[int], y_offsets: list[int], factor: int = 2
+) -> Callable[[Point], Point]:
+    scale = factor - 1
 
-    def manhattan_distance(a: tuple[int, int], b: tuple[int, int]) -> int:
-        return abs(a[0] - b[0]) + abs(a[1] - b[1])
+    def f(p: Point) -> Point:
+        return p + Point(x_offsets[p.x] * scale, y_offsets[p.y] * scale)
 
-    return sum(
-        manhattan_distance(offset(a), offset(b)) for a, b in combinations(points, 2)
-    )
+    return f
 
 
-points = {(x, y) for y, l in enumerate(stdin) for x, c in enumerate(l) if c == "#"}
+points = {Point(x, y) for y, l in enumerate(stdin) for x, c in enumerate(l) if c == "#"}
 
-x_present, y_present = set(p[0] for p in points), set(p[1] for p in points)
+x_present, y_present = set(p.x for p in points), set(p.y for p in points)
 width, height = max(x for x in x_present) + 1, max(y for y in y_present) + 1
 x_offsets = offsets(width, x_present)
 y_offsets = offsets(height, y_present)
 
-print(solve(points, x_offsets, y_offsets))
-print(solve(points, x_offsets, y_offsets, 1000000))
+print(sum(dists(map(offsetter(x_offsets, y_offsets), points))))
+print(sum(dists(map(offsetter(x_offsets, y_offsets, 1000000), points))))
-- 
cgit v1.2.3-54-g00ecf