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Homework Help: Computer programing - making new data types for integers java/c

  1. Jul 14, 2010 #1
    How would I make a new data type that would hold larger numbers than ones that we can currently use?

    for example I need a data type that can handle calculations from large factorials
    200!, = 200*199*198*197 ...................
    it's a really large number and can't be saved in ints/doubles/longs ect...
    so i need to make a new data type,

    how would I do this?

    I know both java and C, but would prefer it if the help was done in java

  2. jcsd
  3. Jul 14, 2010 #2
    google: arbitrary precision arithmetic

    plus java has a BigInteger class already.
  4. Jul 14, 2010 #3

    another note, i'm doing an assignment
    and have been told that i'm not allowed to use biginteger
  5. Jul 14, 2010 #4


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    You already know how -- you do it with pen and paper all the time.

    However, base 65536 or base 4294967296 is probably more convenient than base 10.

    qbert gave you a buzzword for searching. Another one is "multi-precision arithmetic".
  6. Jul 17, 2010 #5
    you will need to use the bit operators( | &) and keep track of the bit pushed off the the lower words and add it to the higher words
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