The versions.alt directory contains the original (unfaulted) version
as well as faulted (mutated) versions.  The versions.orig contains the
original unfaulted version.  The mutants directory contains 200 generated
mutations of the original.  Each of these modified versions is named
mutantN.cc.gz (N=1...200) and represent a single change to the original
source which can be revealed by using a file differencing tool (e.g. diff)

The original version (versions.orig/concordance.cc) also encapsulates the
faulty versions created by the author and students via a manual fault
insertion methodology.  See the README.txt which accompanies this
version for more information on how to activate these faults.

The mutated versions are stored in gzip format to minimize disk space.
To use them remember to uncompress (gunzip) the file prior to running
the GNU C++ compiler.
