-=================================================================
-Matt McCutchen's Big Integer Library
-A C++ library that does arithmetic on integers of unlimited size.
-=================================================================
-Version 2004.12.24.2
-This library contains two classes, BigUnsigned and BigInteger, that represent nonnegative integers and integers, respectively. Each provides the operations listed below and possibly others:
-+, -, *, /, %, unary -
-+=, -=, *=, /=, %=, ++, --
-==, !=, <, <=, >, >=
-&, |, ^
-
-To get started using this library, look at the code in `sample.cc'. Type `make sample' to compile the sample program in `sample.cc' so you can see what it does.
-
-This library includes a makefile. To compile it, just type `make'; you'll get some `.o' files. Include `.hh' files and link with `.o' files as necessary for your programming projects.
-
-Please see the project Web site at
- http://mysite.verizon.net/mccutchen/bigint/
-for more information and the latest version.
-
-Change Log:
-===========
-
-2004.12.24.2 version:
-I tied down a couple of loose ends involving division/modulo. I added an explanation of put-here vs. overloaded operators in the sample program; this has confused too many people. Miscellaneous other improvements.
-
-I believe that, at this point, the Big Integer Library makes no assumptions about the word size of the machine it is using. `BigUnsigned::Blk' is always an `unsigned long', whatever that may be, and its size is computed with `sizeof' when necessary. However, just in case, I would be interested to have someone test the library on a non-32-bit machine to see if it works.
-
-2004.12.24 version:
-This is a _major_ upgrade to the library. Among the things that have changed:
-
-I wrote the original version of the library, particularly the four ``classical algorithms'' in `BigUnsigned.cc', using array indexing. Then I rewrote it to use pointers because I thought that would be faster. But recently, I revisited the code in `BigUnsigned.cc' and found that I could not begin to understand what it was doing.
-
-I have decided that the drawbacks of pointers, increased coding difficulty and reduced code readability, far outweigh their speed benefits. Plus, any modern optimizing compiler should produce fast code either way. Therefore, I rewrote the library to use array indexing again. (Thank goodness for regular-expression find-and-replace. It saved me a lot of time.)
-
-The put-here operations `divide' and `modulo' of each of `BigUnsigned' and `BigInteger' have been supplanted by a single operation `divideWithRemainder'. Read the profuse comments for more information on its exact behavior.
-
-There is a new class `BigUnsignedInABase' that is like `BigUnsigned' but uses a user-specified, small base instead of `256 ^ sizeof(unsigned long)'. Much of the code common to the two has been factored out into `NumberlikeArray'.
-
-`BigUnsignedInABase' facilitates conversion between `BigUnsigned's and digit-by-digit string representations using `std::string'. Convenience routines to do this conversion are in `BigIntegerUtils.hh'. `iostream' compatibility has been improved.
-
-I would like to thank Chris Morbitzer for the e-mail message that catalyzed this major upgrade. He wanted a way to convert a string to a BigInteger. One thing just led to another, roughly in reverse order from how they are listed here.
-
-2004.1216 version:
-Brad Spencer pointed out a memory leak in `BigUnsigned::divide'. It is fixed in the December 16, 2004 version.
-
-2004.1205 version:
-After months of inactivity, I fixed a bug in the `BigInteger' division routine; thanks to David Allen for reporting the bug. I also added simple routines for decimal output to `std::ostream's, and there is a demo that prints out powers of 3.
-
-===================
\ No newline at end of file
+ C++ Big Integer Library
+ (see ChangeLog for version)
+
+ http://mattmccutchen.net/bigint/
+
+ Written and maintained by Matt McCutchen <matt@mattmccutchen.net>
+
+You can use this library in a C++ program to do arithmetic on integers of size
+limited only by your computer's memory. The library provides BigUnsigned and
+BigInteger classes that represent nonnegative integers and signed integers,
+respectively. Most of the C++ arithmetic operators are overloaded for these
+classes, so big-integer calculations are as easy as:
+
+ #include "BigIntegerLibrary.hh"
+
+ BigInteger a = 65536;
+ cout << (a * a * a * a * a * a * a * a);
+
+ (prints 340282366920938463463374607431768211456)
+
+The code in `sample.cc' demonstrates the most important features of the library.
+To get started quickly, read the code and explanations in that file and run it.
+If you want more detail or a feature not shown in `sample.cc', consult the
+consult the actual header and source files, which are thoroughly commented.
+
+This library emphasizes ease of use and clarity of implementation over speed;
+some users will prefer GMP (http://swox.com/gmp/), which is faster. The code is
+intended to be reasonably portable across computers and modern C++ compilers; in
+particular, it uses whatever word size the computer provides (32-bit, 64-bit, or
+otherwise).
+
+Compiling programs that use the library
+---------------------------------------
+The library consists of a folder full of C++ header files (`.hh') and source
+files (`.cc'). Your own programs should `#include' the necessary header files
+and link with the source files. A makefile that builds the sample program
+(`sample.cc') is included; you can adapt it to replace the sample with your own
+program.
+
+Alternatively, you can use your own build system or IDE. In that case, you must
+put the library header files where the compiler will find them and arrange to
+have your program linked with the library source files; otherwise, you will get
+errors about missing header files or "undefined references". To learn how to do
+this, consult the documentation for the build system or IDE; don't bother asking
+me. Adding all the library files to your project will work in many IDEs but may
+not be the most desirable approach.
+
+Resources
+---------
+The library's Web site (above) provides links to released versions, the current
+development version, and a mailing list for release announcements, questions,
+bug reports, and other discussion of the library. I would be delighted to hear
+from you if you like this library and/or find a good use for it.
+
+Bugs and enhancements
+---------------------
+The library has been tested by me and others but is by no means bug-free. If
+you find a bug, please report it, whether it comes in the form of compiling
+trouble, a mathematically inaccurate result, or a memory-management blooper
+(since I use Java, these are altogether too common in my C++). I generally fix
+all reported bugs. You are also welcome to request enhancements, but I am
+unlikely to do substantial amounts of work on enhancements at this point.
+
+Legal
+-----
+I, Matt McCutchen, the sole author of the original Big Integer Library, waive my
+copyright to it, placing it in the public domain. The library comes with
+absolutely no warranty.
+
+~~~~
Matt McCutchen's Web Site / bigint / bigint.git / blobdiff