c3-lang/libtommath/bn_mp_lcm.c

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• Hash : 079b0f65
  Author :
  Date : 2015-10-30T17:55:29
  

  Getting ready for v0.43.0 release Also updated my email address... Signed-off-by: Tom St Denis <tstdenis82@gmail.com>

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• bn_mp_lcm.c

• #include <tommath.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.
   *
   * The library is free for all purposes without any express
   * guarantee it works.
   *
   * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
   */
  
  /* computes least common multiple as |a*b|/(a, b) */
  int mp_lcm (mp_int * a, 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
  
  /* $Source$ */
  /* $Revision$ */
  /* $Date$ */
  

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