// cl_LF_len_incsqrtx().
// General includes.
#include "cl_sysdep.h"
// Specification.
#include "cl_LF.h"
// Implementation.
namespace cln {
uintC cl_LF_len_incsqrtx (uintC n)
{
// Methode bei intDsize=16:
// Allgemein: intDsize*n + sqrt(intDsize*n) + 2 + 31 < intDsize*(n+inc)
// <==> sqrt(intDsize*n) + 33 < intDsize*inc
// <==> sqrt(intDsize*n) < intDsize*inc - 33
// <==> intDsize*n < intDsize^2*inc^2 - 66*intDsize*inc + 1089
// <==> n <= intDsize*inc^2 - 66*inc + floor(1089/intDsize)
return
#define NMAX(k) (uintL)((intDsize*(k)-66)*(k)+floor(1089,intDsize))
#define FITS(n,k) ((intDsize*(k) > 33) && ((n) <= NMAX(k)))
#define n_max (uintL)(bitm(intCsize)-1)
#define TRYINC(inc) FITS(n_max,inc) || FITS(n,inc) ? RETINC(inc) :
#define RETINC(inc) \
/* at this point we know n <= NMAX(inc) */ \
/* Check whether n + (inc) overflows. */ \
((NMAX(inc) <= n_max-(inc)) || (n <= n_max-(inc)) ? n+(inc) : n_max)
#define TEST(i) TRYINC(1UL<<i)
TEST(0)
TEST(1)
TEST(2)
TEST(3)
TEST(4)
TEST(5)
TEST(6)
TEST(7)
TEST(8)
TEST(9)
TEST(10)
TEST(11)
TEST(12)
TEST(13)
// No TEST(14), because NMAX(1UL<<14) is already out of range.
n_max;
}
} // namespace cln
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