24 lines
701 B
Python
24 lines
701 B
Python
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def safe(levels: list[int]) -> bool:
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i = 0
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# figure out the diffs
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diffs = []
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while i < len(levels) - 1:
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curr, nxt = levels[i], levels[i+1]
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diffs.append(curr - nxt)
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i += 1
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if 0 in diffs:
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return False
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neg = len(list(filter(lambda d: d < 0, diffs)))
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pos = len(list(filter(lambda d: d > 0, diffs)))
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big = len(list(filter(lambda d: abs(d) > 3, diffs)))
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if big > 0:
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return False
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return (neg == 0 and pos == len(diffs)) or (neg == len(diffs) and pos == 0)
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with open('1.input') as file:
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reports = [[int(i) for i in line.split()] for line in file]
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print(sum([1 if r else 0 for r in [safe(report) for report in reports]]))
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