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Thread: QBitArray - find first/last set or clean bit

  1. #1
    Join Date
    Jan 2012
    Qt products

    Default QBitArray - find first/last set or clean bit

    How fast do it?
    I must iterate over all bits?
    It will be faster if will possible bits treat at 32 or even 64 bit chunks.

  2. #2
    Join Date
    Jan 2008
    Alameda, CA, USA
    Thanked 856 Times in 843 Posts
    Qt products

    Default Re: QBitArray - find first/last set or clean bit

    I am sure that the internal implementation of QBitArray::testBit() is optimized for this type of operation. Just iterate over the bits from beginning to end or vice-versa. Anything you try to do to optimize this yourself will probably be slower.

    And as the documentation says:

    For technical reasons, it is more efficient to use testBit() and setBit() to access bits in the array than operator[]().
    It would be better to focus on the important parts of your application rather than trying to rewrite basic Qt classes.
    <=== The Great Pumpkin says ===>
    Please use CODE tags when posting source code so it is more readable. Click "Go Advanced" and then the "#" icon to insert the tags. Paste your code between them.

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