From 2bdc480651cbd840abdd80c0acad5dbfa3d62aff Mon Sep 17 00:00:00 2001
From: Luke Hubmayer-Werner <mongoose41@gmail.com>
Date: Fri, 9 Dec 2022 17:00:35 +1030
Subject: [PATCH] Clean up python helpers and day9

---
 2022/day09.py   | 38 ++++++++++++--------------------------
 2022/helpers.py | 22 +++++++++++++++++++---
 2 files changed, 31 insertions(+), 29 deletions(-)

diff --git a/2022/day09.py b/2022/day09.py
index 568e4ae..87dcc6d 100644
--- a/2022/day09.py
+++ b/2022/day09.py
@@ -1,39 +1,25 @@
-import numpy as np
-with open('input/09', 'r') as file:
-	lines = file.read().strip().split('\n')
-dtype = np.int32
+from helpers import *
+lines = read_day(9).split('\n')
 
-directions_array = np.array([[1,0], [-1,0], [0,1], [0,-1]], dtype=dtype)
-directions_dict = {'R': directions_array[0], 'L': directions_array[1], 'D': directions_array[2], 'U': directions_array[3]}  # Positive down for visualization
-
-def move_tail(rope: np.array):
+def move_tail(rope: ArrayLike):
 	for i in range(1, rope.shape[0]):
-		dx, dy = rope[i-1,:] - rope[i,:]
-		if abs(dx) > 1 and dy == 0:
-			rope[i,0] += 1 if dx > 0 else -1
-		elif abs(dy) > 1 and dx == 0:
-			rope[i,1] += 1 if dy > 0 else -1
-		elif abs(dx) + abs(dy) > 2:
-			rope[i,0] += 1 if dx > 0 else -1
-			rope[i,1] += 1 if dy > 0 else -1
+		delta = rope[i-1] - rope[i]
+		abs_delta = abs(delta)
+		if (abs_delta.max() > 1 and abs_delta.min() == 0) or (sum(abs_delta) > 2):
+			rope[i] += np.sign(delta)
 
 def simulate_rope_drag(length: int, lines: list[str]):
 	rope = np.zeros([length,2], dtype=dtype)
-	visited = {(rope[-1,0], rope[-1,1])}
+	visited = {tuple(rope[-1])}
 	for line in lines:
 		dir_vector = directions_dict[line[0]]
 		amount = int(line[2:])
 		for i in range(amount):
-			rope[0,:] += dir_vector
+			rope[0] += dir_vector
 			move_tail(rope)
-			visited.add((rope[-1,0], rope[-1,1]))
+			visited.add(tuple(rope[-1]))
 	return visited
 
-def visualise_cells(visited: set, size=20):
-	vis_lol = [['#' if (x,y) in visited else '.' for x in range(-size, size)] for y in range(-size, size)]
-	vis_str = '\n'.join(''.join(line) for line in vis_lol)
-	print(vis_str)
-
 
 visited_part_1 = simulate_rope_drag(2, lines)
 print(f'Part 1: String length of 2 - tail visits {len(visited_part_1)} cells')
@@ -41,7 +27,7 @@ visited_part_2 = simulate_rope_drag(10, lines)
 print(f'Part 2: String length of 10 - tail visits {len(visited_part_2)} cells')
 
 if input('Visualise part 1 cells? [y/N]: ').lower() == 'y':
-	visualise_cells(visited_part_1, 70)
+	visualise_sparse_cells_set(visited_part_1, 70)
 	print()
 if input('Visualise part 2 cells? [y/N]: ').lower() == 'y':
-	visualise_cells(visited_part_2, 70)
+	visualise_sparse_cells_set(visited_part_2, 70)
diff --git a/2022/helpers.py b/2022/helpers.py
index 195735d..4adec52 100644
--- a/2022/helpers.py
+++ b/2022/helpers.py
@@ -1,11 +1,27 @@
+import numpy as np
+from numpy.typing import ArrayLike
 import re
 numbers_pattern = re.compile(r'((?:(?<!\d)-)?\d+)')
 
 def line_to_numbers(line):
-    return [int(x) for x in numbers_pattern.findall(line)]
+	return [int(x) for x in numbers_pattern.findall(line)]
 
 def lines_to_numbers(lines):
-    return [line_to_numbers(line) for line in lines]
+	return [line_to_numbers(line) for line in lines]
 
 def transpose_array_of_strings(aos, reverse_x = False, reverse_y = False, strip = ''):
-    return [''.join(l[i] for l in aos[::-1 if reverse_y else 1]).strip(strip) for i in range(len(aos[0]))[::-1 if reverse_x else 1]]
+	return [''.join(l[i] for l in aos[::-1 if reverse_y else 1]).strip(strip) for i in range(len(aos[0]))[::-1 if reverse_x else 1]]
+
+def read_day(day):
+	with open(f'input/{day:02}', 'r') as file:
+		return file.read().strip()
+
+dtype = np.int32
+
+directions_array = np.array([[1,0], [-1,0], [0,1], [0,-1]], dtype=dtype)
+directions_dict = {'R': directions_array[0], 'L': directions_array[1], 'D': directions_array[2], 'U': directions_array[3]}  # Positive down for visualization
+
+def visualise_sparse_cells_set(cells: set, size=20, sym_hit='#', sym_miss='.'):
+	vis_lol = [[sym_hit if (x,y) in cells else sym_miss for x in range(-size, size)] for y in range(-size, size)]
+	vis_str = '\n'.join(''.join(line) for line in vis_lol)
+	print(vis_str)