From c217d7b24acdfab094e1c279db13bb972a7696d4 Mon Sep 17 00:00:00 2001
From: Sebastian Seedorf <sseedorf@eclassifiedsgroup.com>
Date: Mon, 13 Dec 2021 09:58:19 +0100
Subject: [PATCH] Day 13 (glamorized)

---
 day13/part1.py |  9 ++++-----
 day13/part2.py | 13 +++++--------
 2 files changed, 9 insertions(+), 13 deletions(-)

diff --git a/day13/part1.py b/day13/part1.py
index b42118b..b8cb133 100644
--- a/day13/part1.py
+++ b/day13/part1.py
@@ -2,16 +2,15 @@
 
 lines = (x.strip() for x in open("input.txt"))
 points = set()
-# 1311,895
 
 for line in lines:
     if line.startswith("fold along x="):
-        mark = int(line[13:])
-        points = set((x if mark > x else 2*mark-x, y) for x, y in points if mark != x)
+        fold = int(line[13:])
+        points = set((fold - abs(x-fold), y) for x, y in points if fold != x)
         break
     elif line.startswith("fold along y="):
-        mark = int(line[13:])
-        points = set((x, y if mark > y else 2*mark-y) for x, y in points if mark != y)
+        fold = int(line[13:])
+        points = set((x, fold - abs(y-fold)) for x, y in points if fold != y)
         break
     elif len(line) > 0:
         points.add(tuple(int(num) for num in line.split(",")))
diff --git a/day13/part2.py b/day13/part2.py
index 0143855..7af6a19 100644
--- a/day13/part2.py
+++ b/day13/part2.py
@@ -1,21 +1,18 @@
 #!/usr/bin/env python3
-from functools import reduce
-import numpy as np
 
 lines = (x.strip() for x in open("input.txt"))
 points = set()
-# 1311,895
 
 for line in lines:
     if line.startswith("fold along x="):
-        mark = int(line[13:])
-        points = set((x if mark > x else 2*mark-x, y) for x, y in points if mark != x)
+        fold = int(line[13:])
+        points = set((fold - abs(x-fold), y) for x, y in points if fold != x)
     elif line.startswith("fold along y="):
-        mark = int(line[13:])
-        points = set((x, y if mark > y else 2*mark-y) for x, y in points if mark != y)
+        fold = int(line[13:])
+        points = set((x, fold - abs(y-fold)) for x, y in points if fold != y)
     elif len(line) > 0:
         points.add(tuple(int(num) for num in line.split(",")))
 
-max_x, max_y = reduce(lambda p, c: tuple(map(max, zip(p, c))), points)
+max_x, max_y = tuple(map(max, zip(*points)))
 for line in (''.join('#' if (x, y) in points else ' ' for x in range(max_x+1)) for y in range(max_y+1)):
     print(line)