30 lines
1.1 KiB
Python
30 lines
1.1 KiB
Python
class Solution:
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def isMonotonic(self, nums: List[int]) -> bool:
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# Means difference between two nums indicate that it is
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# decreasing or that difference is 0
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isNonIncreasing = True
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# Same idea as above butnopposite: it is either increasing
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# or difference is 0
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isNonDecreasing = True
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for i in range(1, len(nums)):
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difference = nums[i] - nums[i - 1]
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# We can say with confidence if this condition ever passes
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# that sequence is increasing (e.g. 1 2 4 8 ...)
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if difference > 0:
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isNonIncreasing = False
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# Sequence is decreasing (e.g. 1 0 -2 -4 ...)
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elif difference < 0:
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isNonDecreasing = False
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# If both flags are set to False, that means there is no
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# monotonous state and we can break early.
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if not isNonIncreasing and not isNonDecreasing:
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return False
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# At the end, if either flag remains True, we have a montonous
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# array
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return isNonIncreasing or isNonDecreasing
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