My Advent of Code solutions in Python.
kevinyap.ca/2019/12/going-fast-in-advent-of-code/
advent-of-code
python
Add solution for 2023/03
+41
+41
2023/day03.py
+41
2023/day03.py
···
1
+
import fileinput
2
+
3
+
SYMBOLS = {}
4
+
PARTS = []
5
+
6
+
# Parse input.
7
+
for y, line in enumerate(fileinput.input()):
8
+
num = ''
9
+
start = None
10
+
for x, c in enumerate(line.strip()):
11
+
if not c.isdigit() and c != '.':
12
+
SYMBOLS[x, y] = c
13
+
14
+
if c.isdigit():
15
+
if not num:
16
+
start = x
17
+
num += c
18
+
elif num:
19
+
PARTS.append((int(num), y, start, x - 1))
20
+
num = ''
21
+
22
+
if num:
23
+
PARTS.append((int(num), y, start, x - 1))
24
+
25
+
# Solve problem.
26
+
part_1_seen = set()
27
+
part_2 = 0
28
+
29
+
for x, y in SYMBOLS:
30
+
adj = []
31
+
for i, (n, yy, start, end) in enumerate(PARTS):
32
+
if yy - 1 <= y <= yy + 1 and start - 1 <= x <= end + 1:
33
+
part_1_seen.add(i)
34
+
adj.append(n)
35
+
36
+
if len(adj) == 2 and SYMBOLS[x, y] == '*':
37
+
part_2 += adj[0] * adj[1]
38
+
39
+
40
+
print("Part 1:", sum(PARTS[i][0] for i in part_1_seen))
41
+
print("Part 2:", part_2)