Skip to content

Commit fe803f4

Browse files
askmeegsaskmeegs
committed
A convoluted day 13
1 parent b81bba0 commit fe803f4

File tree

1 file changed

+181
-28
lines changed

1 file changed

+181
-28
lines changed

‎day-13/part-two.py

Lines changed: 181 additions & 28 deletions
Original file line numberDiff line numberDiff line change
@@ -1,4 +1,155 @@
11
"""
2+
You're given a series of patterns like this -
3+
4+
#.##..##.
5+
..#.##.#.
6+
##......#
7+
##......#
8+
..#.##.#.
9+
..##..##.
10+
#.#.##.#.
11+
12+
Task - find the line of reflection (either row or col)
13+
Here, it's the vertical line between cols 5 and 6.
14+
15+
A vertical line of reflection means that the reflected columns
16+
going left and right from the LOR are identical.
17+
18+
A horizontal line of reflection is the same, but for rows going up/down.
19+
In this case:
20+
21+
#...##..#
22+
#....#..#
23+
..##..###
24+
#####.##.
25+
#####.##.
26+
..##..###
27+
#....#..#
28+
29+
The line of reflection is horizontal, after row 4.
30+
31+
TASK: iterate through each pattern in input.
32+
Then, create a summary by:
33+
- For every VLOR - Sum- the # of cols to the left of each VERTICAL LOR (where applicable)
34+
- For every HLOR - Sum- (100 * # of rows above each HORIZONTAL LOR)
35+
- Sum those 2 results.
36+
37+
The answer to small is 405.
38+
"""
39+
40+
def pp(L):
41+
for l in L:
42+
print(l)
43+
print("----------------------------------")
44+
45+
inp = []
46+
with open("input.txt") as f:
47+
lines = f.readlines()
48+
49+
i = 0
50+
inp = []
51+
t = []
52+
while i < len(lines):
53+
L = lines[i].strip()
54+
# if L is a blank line
55+
if "#" not in L and "." not in L:
56+
inp.append(t)
57+
t = []
58+
else:
59+
t.append(L)
60+
i += 1
61+
inp.append(t)
62+
63+
64+
# Run computation
65+
# after column c - 0 indexed
66+
vlors = []
67+
68+
# after row r - 0 indexed
69+
hlors = []
70+
71+
72+
# [h, -1]
73+
part1_answers = {}
74+
for i in range(0, len(inp)):
75+
part1_answers[i] = ["z", -1]
76+
77+
# COMPARE ROWS - HORIZONTAL LINE OF REFLECTION?
78+
def check_hlor(s1, s2):
79+
i = len(s1) - 1
80+
j = 0
81+
# i => s1, walk backwards
82+
while i >= 0 and j < len(s2):
83+
print("i={}, j={}, s1[i]={}, s2[j]={}".format(i, j, s1[i], s2[j]))
84+
if s1[i] != s2[j]:
85+
return False
86+
i -= 1
87+
j += 1
88+
return True
89+
90+
for idx, i in enumerate(inp):
91+
# print("\n\n 🏁 STARTING INPUT {}".format(i))
92+
hlor = False
93+
# check rows for HLOR
94+
r = 1
95+
while r < len(i):
96+
s1 = i[:r]
97+
s2 = i[r:]
98+
# print("\n↔️ r={}, checking horiz line of reflection for \ns1={}\ns2={}".format(r, s1, s2))
99+
if check_hlor(s1, s2):
100+
hlors.append(r)
101+
hlor = True
102+
part1_answers[idx] = ["h", r]
103+
# print("✅ input {} has hlor after row {}".format(i, r))
104+
break
105+
r += 1
106+
if hlor:
107+
continue
108+
109+
# create a copy of i, rotated 90 degrees to the right
110+
# this will be used to check for VLOR
111+
i90 = list(zip(*i[::-1]))
112+
# convert list of tuples to list of strings
113+
i90 = ["".join(t) for t in i90]
114+
115+
116+
print("ROTATED 90 DEGREES")
117+
pp(i90)
118+
r = 1
119+
vlor = False
120+
while r < len(i90):
121+
s1 = i90[:r]
122+
s2 = i90[r:]
123+
# print("\nr={}, checking vert line of reflection for \ns1={}\ns2={}".format(r, s1, s2))
124+
if check_hlor(s1, s2):
125+
vlors.append(r)
126+
vlor = True
127+
part1_answers[idx] = ["v", r]
128+
# print("✅ input {} has hlor after row {}".format(i, r))
129+
break
130+
r += 1
131+
132+
if not vlor and not hlor:
133+
print("\n ⚠️ input at index {} has no VLOR or HLOR:".format(idx))
134+
pp(i)
135+
# calculate summary
136+
"""
137+
TASK: iterate through each pattern in input.
138+
Then, create a summary by:
139+
- For every VLOR - Sum- the # of cols to the left of each VERTICAL LOR (where applicable)
140+
- For every HLOR - Sum- (100 * # of rows above each HORIZONTAL LOR)
141+
- Sum those 2 results.
142+
"""
143+
144+
# after row, after col
145+
res = 0
146+
for h in hlors:
147+
res += 100 * h
148+
for v in vlors:
149+
res += v
150+
print("⭐️ PART 1 res={}".format(res))
151+
print(part1_answers)
152+
"""
2153
PART TWO
3154
Every mirror has exactly one smudge - one # or . is incorrect and should
4155
be the opposite type.
@@ -16,7 +167,7 @@
16167
..##..##.
17168
#.#.##.#.
18169
19-
If hte top left "#" were "." instead, we'd have a different line of reflection.
170+
If the top left "#" were "." instead, we'd have a different line of reflection.
20171
21172
..##..##.
22173
..#.##.#.
@@ -35,7 +186,7 @@ def pp(L):
35186

36187

37188
inp = []
38-
with open("small.txt") as f:
189+
with open("input.txt") as f:
39190
lines = f.readlines()
40191

41192
i = 0
@@ -95,13 +246,16 @@ def create_perms(i):
95246
perms = create_perms(i)
96247
found_lor = False
97248
p_index = 0
98-
min_lor = 1000
99-
hor_lor = False
100249
while not found_lor:
101250
hlor = False
102251
r = 1
103-
cur = perms[p_index]
252+
cur = perms[p_index]
253+
print("\n\ni=")
254+
pp(i)
255+
print("cur=")
256+
pp(cur)
104257
while r < len(i):
258+
print("r={}".format(r))
105259
s1 = cur[:r]
106260
s2 = cur[r:]
107261
# print("\nevaluating cur where r={}".format(r))
@@ -111,17 +265,17 @@ def create_perms(i):
111265
# print("and s2=")
112266
# pp(s2)
113267
if check_hlor(s1, s2):
114-
# hlors.append(r)
115-
hlor = True
116-
found_lor = True
117-
print("✅ input {} has hlor after row {}".format(i, r))
118-
if r < min_lor:
119-
min_lor = r
120-
hor_lor = True
121-
break
268+
if part1_answers[idx][0] == "h" and part1_answers[idx][1] == r:
269+
print("hlor can't be the same as part 1")
270+
else:
271+
hlor = True
272+
found_lor = True
273+
hlors.append(r)
274+
print("✅ input has hlor after row {}".format(r))
275+
pp(s1)
276+
pp(s2)
277+
break
122278
r += 1
123-
if hlor:
124-
continue
125279

126280
# create a copy of i, rotated 90 degrees to the right
127281
# this will be used to check for VLOR
@@ -138,22 +292,21 @@ def create_perms(i):
138292
s2 = i90[r:]
139293
# print("\nr={}, checking vert line of reflection for \ns1={}\ns2={}".format(r, s1, s2))
140294
if check_hlor(s1, s2):
141-
# vlors.append(r)
142-
vlor = True
143-
found_lor = True
144-
print("✅ input {} has vlor after row {}".format(i, r))
145-
if r < min_lor:
146-
min_lor = r
147-
hor_lor = False
148-
break
295+
if part1_answers[idx][0] == "v" and part1_answers[idx][1] == r:
296+
print("vlor can't be the same as part 1")
297+
else:
298+
vlor = True
299+
found_lor = True
300+
print("✅ input {} has vlor after row {}".format(cur, r))
301+
vlors.append(r)
302+
break
149303
r += 1
150-
if hor_lor:
151-
hlors.append(min_lor)
152-
else:
153-
vlors.append(min_lor)
154-
p_index += 1
304+
p_index += 1
155305

156306
# after row, after col
307+
print("done iterating")
308+
print("hlors={}".format(hlors))
309+
print("vlors={}".format(vlors))
157310
res = 0
158311
for h in hlors:
159312
res += 100 * h

0 commit comments

Comments
 (0)