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Puzzle 23
There Is a Question in There Somewhere |
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Where do these puzzles come from? |
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One of my goals for this book was to develop puzzles that are real. What do I mean by this? I've sometimes found that sample code in books is somewhat artificial. For example, object-oriented programming is demonstrated by using animalsyou have a class named Animal with inherited classes that are specific types of animals, such as dog or cat. This is fine if you're running a zoo, but let's face it: Most programmers don't create software for zoos. They may work in offices that bear some resemblance to zoos, but I digress. My point is that book examples are sometimes just a bit irrelevant. |
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With this book, I'm fairly confident I've avoided that trap. How can I be so sure? Rather than explain, I thought I would demonstrate. Consider this, if you will, a puzzle on how to create these types of puzzles. |
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First, the inspiration for the puzzle. |
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The following is a real inquiry I received about two days ago: |
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Dan, you've been very helpful in the pastI'm hoping you can help with what I'm sure is actually a simple question. |
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I'm trying to use the user_info_2 structure with the NetAddUser function from VBA. Part of this structure is: PBYTE usri2_logon_hours; points to a 21-byte (168 bits) bit string that specifies . . . |
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How do I include this in my type declaration? Also, there is a constant in the C header as: |
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#define USER_MAXSTORAGE_UNLIMITED ((unsigned long)-1L) |
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Isn't this a contradiction? |
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Should I just declare this as a long constant with the value of 1? Thanks in advance! |
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Now, I don't want to give you the impression that I answer all of the questions I receive. Time does not permit me to answer more than a few. In this case, however, the question struck me as perfect for this book. I gave my correspondent a |
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