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#include "tommath_private.h"
#ifdef BN_MP_LCM_C
/* LibTomMath, multiple-precision integer library -- Tom St Denis
*
* LibTomMath is a library that provides multiple-precision
* integer arithmetic as well as number theoretic functionality.
*
* The library was designed directly after the MPI library by
* Michael Fromberger but has been written from scratch with
* additional optimizations in place.
*
* SPDX-License-Identifier: Unlicense
*/
/* computes least common multiple as |a*b|/(a, b) */
int mp_lcm(const mp_int *a, const mp_int *b, mp_int *c)
{
int res;
mp_int t1, t2;
if ((res = mp_init_multi(&t1, &t2, NULL)) != MP_OKAY) {
return res;
}
/* t1 = get the GCD of the two inputs */
if ((res = mp_gcd(a, b, &t1)) != MP_OKAY) {
goto LBL_T;
}
/* divide the smallest by the GCD */
if (mp_cmp_mag(a, b) == MP_LT) {
/* store quotient in t2 such that t2 * b is the LCM */
if ((res = mp_div(a, &t1, &t2, NULL)) != MP_OKAY) {
goto LBL_T;
}
res = mp_mul(b, &t2, c);
} else {
/* store quotient in t2 such that t2 * a is the LCM */
if ((res = mp_div(b, &t1, &t2, NULL)) != MP_OKAY) {
goto LBL_T;
}
res = mp_mul(a, &t2, c);
}
/* fix the sign to positive */
c->sign = MP_ZPOS;
LBL_T:
mp_clear_multi(&t1, &t2, NULL);
return res;
}
#endif
/* ref: HEAD -> master, tag: v1.1.0 */
/* git commit: 08549ad6bc8b0cede0b357a9c341c5c6473a9c55 */
/* commit time: 2019-01-28 20:32:32 +0100 */
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