My Advent of Code solutions in Python.
kevinyap.ca/2019/12/going-fast-in-advent-of-code/
advent-of-code
python
Add 2017/14
+65
+62
2017/day14.py
+62
2017/day14.py
···
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import fileinput
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from utils import Point
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def knot_hash(msg):
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lengths = [ord(x) for x in msg] + [17, 31, 73, 47, 23]
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sparse = range(0, 256)
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pos = 0
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skip = 0
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for _ in range(64):
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for l in lengths:
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for i in range(l // 2):
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x = (pos + i) % len(sparse)
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y = (pos + l - i - 1) % len(sparse)
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sparse[x], sparse[y] = sparse[y], sparse[x]
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pos = pos + l + skip % len(sparse)
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skip += 1
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sparse = sparse
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dense = []
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for i in range(16):
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res = 0
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for j in range(0, 16):
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res ^= sparse[(i * 16) + j]
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dense.append(res)
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return ''.join('%02x' % x for x in dense)
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KEY_STRING = fileinput.input()[0].strip()
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DISK = set()
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for x in range(128):
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hash_hex = knot_hash(KEY_STRING + '-' + str(x))
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hash_bits = ''.join('{0:04b}'.format(int(x, 16)) for x in hash_hex)
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for y, b in enumerate(hash_bits):
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if b == '1':
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DISK.add(Point(x, y))
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regions = 0
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seen = set()
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for p in DISK:
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if p in seen:
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continue
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queue = [p]
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while queue:
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np = queue.pop()
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seen.add(np)
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for n in np.neighbours_4():
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if n in DISK and n not in seen:
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queue.append(n)
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regions += 1
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print "Number of used squares:", len(DISK)
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print "Number of regions:", regions
+1
2017/inputs/14.txt
+1
2017/inputs/14.txt
···
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nbysizxe