1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
|
/* mpz_lcm -- mpz/mpz least common multiple.
Copyright 1996, 2000, 2001, 2005 Free Software Foundation, Inc.
This file is part of the GNU MP Library.
The GNU MP Library is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 3 of the License, or (at your
option) any later version.
The GNU MP Library is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
License for more details.
You should have received a copy of the GNU Lesser General Public License
along with the GNU MP Library. If not, see http://www.gnu.org/licenses/. */
#include "gmp.h"
#include "gmp-impl.h"
#include "longlong.h"
void
mpz_lcm (mpz_ptr r, mpz_srcptr u, mpz_srcptr v)
{
mpz_t g;
mp_size_t usize, vsize, size;
TMP_DECL;
usize = SIZ (u);
vsize = SIZ (v);
if (usize == 0 || vsize == 0)
{
SIZ (r) = 0;
return;
}
usize = ABS (usize);
vsize = ABS (vsize);
if (vsize == 1)
{
mp_limb_t vl, gl, c;
mp_srcptr up;
mp_ptr rp;
one:
MPZ_REALLOC (r, usize+1);
up = PTR(u);
vl = PTR(v)[0];
gl = mpn_gcd_1 (up, usize, vl);
vl /= gl;
rp = PTR(r);
c = mpn_mul_1 (rp, up, usize, vl);
rp[usize] = c;
usize += (c != 0);
SIZ(r) = usize;
return;
}
if (usize == 1)
{
usize = vsize;
MPZ_SRCPTR_SWAP (u, v);
goto one;
}
TMP_MARK;
size = MAX (usize, vsize);
MPZ_TMP_INIT (g, size);
mpz_gcd (g, u, v);
mpz_divexact (g, u, g);
mpz_mul (r, g, v);
SIZ (r) = ABS (SIZ (r)); /* result always positive */
TMP_FREE;
}
|
