       Copyright © 1990-2001 by George Williams

       Redistribution and use in source and binary forms, with or without
       modification, are permitted provided that the following conditions are
       met:

       Redistributions of source code must retain the above copyright notice,
       this list of conditions and the following disclaimer.

       Redistributions in binary form must reproduce the above copyright
       notice, this list of conditions and the following disclaimer in the
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       The name of the author may not be used to endorse or promote products
       derived from this software without specific prior written permission.

       THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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       (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
       SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
       HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
       STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
       IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
       POSSIBILITY OF SUCH DAMAGE.
