NetBSD/usr.bin/yacc/warshall.c

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#ifndef lint
static char rcsid[] = "$Id: warshall.c,v 1.3 1993/08/02 17:56:52 mycroft Exp $";
#endif /* not lint */
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#include "defs.h"
transitive_closure(R, n)
unsigned *R;
int n;
{
register int rowsize;
register unsigned i;
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register unsigned *rowj;
register unsigned *rp;
register unsigned *rend;
register unsigned *ccol;
register unsigned *relend;
register unsigned *cword;
register unsigned *rowi;
rowsize = WORDSIZE(n);
relend = R + n*rowsize;
cword = R;
i = 0;
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rowi = R;
while (rowi < relend)
{
ccol = cword;
rowj = R;
while (rowj < relend)
{
if (*ccol & (1 << i))
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{
rp = rowi;
rend = rowj + rowsize;
while (rowj < rend)
*rowj++ |= *rp++;
}
else
{
rowj += rowsize;
}
ccol += rowsize;
}
if (++i >= BITS_PER_WORD)
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{
i = 0;
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cword++;
}
rowi += rowsize;
}
}
reflexive_transitive_closure(R, n)
unsigned *R;
int n;
{
register int rowsize;
register unsigned i;
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register unsigned *rp;
register unsigned *relend;
transitive_closure(R, n);
rowsize = WORDSIZE(n);
relend = R + n*rowsize;
i = 0;
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rp = R;
while (rp < relend)
{
*rp |= (1 << i);
if (++i >= BITS_PER_WORD)
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{
i = 0;
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rp++;
}
rp += rowsize;
}
}