My Advent of Code solutions in Python.
kevinyap.ca/2019/12/going-fast-in-advent-of-code/
advent-of-code
python
Update 2024/05
+7
-9
+7
-9
2024/day05.py
+7
-9
2024/day05.py
···
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return lst[(len(lst) - 1) // 2]
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+
# Parse problem input.
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on_updates = False
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graph = defaultdict(set)
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updates = []
···
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if is_unordered(graph, update) == -1:
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part_1 += mid(update)
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else:
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-
while True:
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swap = False
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for i, n in enumerate(update):
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afters = update[i+1:]
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if any(n in graph[a] for a in afters):
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update[i], update[i + 1] = update[i + 1], update[i]
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swap = True
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if not swap:
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break
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# Sort based on how many pages in `updates` should come after a given page.
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afters = {}
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for i, n in enumerate(update):
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afters[n] = len(graph[n] & (set(update) - set([n])))
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update.sort(key=afters.get)
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part_2 += mid(update)
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