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#include "tommath_private.h"
#ifdef BN_MP_LCM_C
/* LibTomMath, multiple-precision integer library -- Tom St Denis */
/* SPDX-License-Identifier: Unlicense */
/* computes least common multiple as |a*b|/(a, b) */
mp_err mp_lcm(const mp_int *a, const mp_int *b, mp_int *c)
{
mp_err err;
mp_int t1, t2;
if ((err = mp_init_multi(&t1, &t2, NULL)) != MP_OKAY) {
return err;
}
/* t1 = get the GCD of the two inputs */
if ((err = 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 ((err = mp_div(a, &t1, &t2, NULL)) != MP_OKAY) {
goto LBL_T;
}
err = mp_mul(b, &t2, c);
} else {
/* store quotient in t2 such that t2 * a is the LCM */
if ((err = mp_div(b, &t1, &t2, NULL)) != MP_OKAY) {
goto LBL_T;
}
err = mp_mul(a, &t2, c);
}
/* fix the sign to positive */
c->sign = MP_ZPOS;
LBL_T:
mp_clear_multi(&t1, &t2, NULL);
return err;
}
#endif
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