My Advent of Code solutions in Python.
kevinyap.ca/2019/12/going-fast-in-advent-of-code/
advent-of-code
python
Use utils.knot_hash in 2017/14 solution
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-34
+1
-30
2017/day14.py
+1
-30
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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from utils import Point, knot_hash
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KEY_STRING = fileinput.input()[0].strip()
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-4
2017/utils.py
+3
-4
2017/utils.py
···
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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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hash_val = 0
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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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hash_val += res << ((16 - i - 1) * 8)
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return ''.join('%02x' % x for x in dense)
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return '%032x' % hash_val
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@total_ordering