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This is a discussion on Password within the C++ Programming forums, part of the General Programming Boards category; Unless of course you wanted to write the number out in base 5...

  1. #46
    & the hat of GPL slaying Thantos's Avatar
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    Unless of course you wanted to write the number out in base 5

  2. #47
    Code Goddess Prelude's Avatar
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    I must have missed something. Was that a requirement, or do you just work with base 5 a lot?
    My best code is written with the delete key.

  3. #48
    & the hat of GPL slaying Thantos's Avatar
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    Yeah its for when I work with pennies, nickles, and quarters. One of my professors just loves base conversions. I had to do it in pascal and in assembly. The "Read in a base 9 number and output it as a base 7 number." Fun stuff

  4. #49
    Cat without Hat CornedBee's Avatar
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    Oh, I had to do that in Haskell. Any base between 2 and 36, and then base -2 for good measure. (Now THAT's a weird number system.)
    All the buzzt!
    CornedBee

    "There is not now, nor has there ever been, nor will there ever be, any programming language in which it is the least bit difficult to write bad code."
    - Flon's Law

  5. #50
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    How do you have a negative base? The base is suppose to represent the number of different symbols that are used.

    In pascal I once did a base (26*2 + 10) 62 system

  6. #51
    Cat without Hat CornedBee's Avatar
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    No, in the definition my professor used, a number system is done like so:
    number = SUM[i = 0 to digit-count](base^i * digit-value)

    So base can be any integer except -1, 0 and 1, as long as you have enough digit signs.

    In base -2, with four digits you get these numbers:
    0000 = 0
    0001 = 1
    0010 = -2
    0011 = -1
    0100 = 4
    0101 = 5
    0110 = 2
    0111 = 3
    1000 = -8
    1001 = -7
    1010 = -10
    1011 = -9
    1100 = -4
    1101 = -3
    1110 = -6
    1111 = -5
    etc. etc.
    All the buzzt!
    CornedBee

    "There is not now, nor has there ever been, nor will there ever be, any programming language in which it is the least bit difficult to write bad code."
    - Flon's Law

  7. #52
    & the hat of GPL slaying Thantos's Avatar
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    I think your professor had to dig deep in his arse to find that defination

  8. #53
    Cat without Hat CornedBee's Avatar
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    Well...

    The "negabinary" system is listed at Wikipedia as a "positional-like system with non-standard base". The German Wikipedia states in a paragraph that as a generalization of numbering systems, the base need not be a natural number as longas the absolute value of the base is greater than 1.
    http://en.wikipedia.org/wiki/Negabinary

    I even had to implement the addition.
    All the buzzt!
    CornedBee

    "There is not now, nor has there ever been, nor will there ever be, any programming language in which it is the least bit difficult to write bad code."
    - Flon's Law

  9. #54
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    Hmm interesting. Though something doesn't seem right
    unusual property that negative and positive numbers can be represented without a sign bit
    but it still takes 1 extra bit.

  10. #55
    and the hat of wrongness Salem's Avatar
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    This has gone way too off-topic.

    Sportsmaniac, if you're still stuck, start a new thread with your latest code and question(s).

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