Exemplo n.º 1
0
static
void RecFindRoots(vec_GF2E& x, const GF2EX& f)
{
   if (deg(f) == 0) return;

   if (deg(f) == 1) {
      long k = x.length();
      x.SetLength(k+1);
      x[k] = ConstTerm(f);
      return;
   }
      
   GF2EX h;

   GF2E r;

   
   {
      GF2EXModulus F;
      build(F, f);

      do {
         random(r);
         clear(h);
         SetCoeff(h, 1, r);
         TraceMap(h, h, F);
         GCD(h, h, f);
      } while (deg(h) <= 0 || deg(h) == deg(f));
   }

   RecFindRoots(x, h);
   div(h, f, h); 
   RecFindRoots(x, h);
}
void FindRoots(vec_ZZ_pE& x, const ZZ_pEX& ff)
{
   ZZ_pEX f = ff;

   if (!IsOne(LeadCoeff(f)))
      LogicError("FindRoots: bad args");

   x.SetMaxLength(deg(f));
   x.SetLength(0);
   RecFindRoots(x, f);
}
Exemplo n.º 3
0
void FindRoots(vec_GF2E& x, const GF2EX& ff)
{
   GF2EX f = ff;

   if (!IsOne(LeadCoeff(f)))
      Error("FindRoots: bad args");

   x.SetMaxLength(deg(f));
   x.SetLength(0);
   RecFindRoots(x, f);
}
static
void RecFindRoots(vec_ZZ_pE& x, const ZZ_pEX& f)
{
   if (deg(f) == 0) return;

   if (deg(f) == 1) {
      long k = x.length();
      x.SetLength(k+1);
      negate(x[k], ConstTerm(f));
      return;
   }
      
   ZZ_pEX h;

   ZZ_pEX r;

   
   {
      ZZ_pEXModulus F;
      build(F, f);

      do {
         random(r, deg(F));
         if (IsOdd(ZZ_pE::cardinality())) {
            PowerMod(h, r, RightShift(ZZ_pE::cardinality(), 1), F);
            sub(h, h, 1);
         }
         else {
            AbsTraceMap(h, r, F);
         }
         GCD(h, h, f);
      } while (deg(h) <= 0 || deg(h) == deg(f));
   }

   RecFindRoots(x, h);
   div(h, f, h); 
   RecFindRoots(x, h);
}
Exemplo n.º 5
0
static
void RecFindRoots(vec_ZZ_p& x, const ZZ_pX& f)
{
   if (deg(f) == 0) return;

   if (deg(f) == 1) {
      long k = x.length();
      x.SetLength(k+1);
      negate(x[k], ConstTerm(f));
      return;
   }
      
   ZZ_pX h;

   ZZ_p r;
   ZZ p1;


   RightShift(p1, ZZ_p::modulus(), 1);
   
   {
      ZZ_pXModulus F;
      build(F, f);

      do {
         random(r);
         PowerXPlusAMod(h, r, p1, F);
         add(h, h, -1);
         GCD(h, h, f);
      } while (deg(h) <= 0 || deg(h) == deg(f));
   }

   RecFindRoots(x, h);
   div(h, f, h); 
   RecFindRoots(x, h);
}