minix/commands/byacc/warshall.c
2009-11-09 10:26:00 +00:00

82 lines
1.2 KiB
C

#include "defs.h"
transitive_closure(R, n)
unsigned *R;
int n;
{
register int rowsize;
register unsigned i;
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;
rowi = R;
while (rowi < relend)
{
ccol = cword;
rowj = R;
while (rowj < relend)
{
if (*ccol & (1 << i))
{
rp = rowi;
rend = rowj + rowsize;
while (rowj < rend)
*rowj++ |= *rp++;
}
else
{
rowj += rowsize;
}
ccol += rowsize;
}
if (++i >= BITS_PER_WORD)
{
i = 0;
cword++;
}
rowi += rowsize;
}
}
reflexive_transitive_closure(R, n)
unsigned *R;
int n;
{
register int rowsize;
register unsigned i;
register unsigned *rp;
register unsigned *relend;
transitive_closure(R, n);
rowsize = WORDSIZE(n);
relend = R + n*rowsize;
i = 0;
rp = R;
while (rp < relend)
{
*rp |= (1 << i);
if (++i >= BITS_PER_WORD)
{
i = 0;
rp++;
}
rp += rowsize;
}
}