ZZn6& ZZn6::powq(void)
{
ZZn X;
copy(get_mip()->sru,X.getzzn());
a.powq(); b.powq();
b*=X;
return *this;
}
ostream& operator<<(ostream& s,const Ps_ZZn& p)
{
BOOL first=TRUE;
ZZn a;
term_ps_zzn *ptr=p.start;
int pw;
if (ptr==NULL)
{
s << "0";
return s;
}
while (ptr!=NULL)
{
a=ptr->an;
if (a.iszero())
{
ptr=ptr->next;
continue;
}
if ((Big)a < get_modulus()/2)
{
a=(-a);
s << " - ";
}
else if (!first) s << " + ";
first=FALSE;
pw=ptr->n*p.pwr-p.offset;
if (pw==0)
{
s << a;
ptr=ptr->next;
continue;
}
if (a==(ZZn)1) s << "x";
else s << a << "*x";
if (pw!=1) s << "^" << pw;
ptr=ptr->next;
}
return s;
}
void ZZn3::get(ZZn& x) const
{{copy(fn.a,x.getzzn());}}
void ZZn3::get(ZZn& x,ZZn& y,ZZn& z) const
{copy(fn.a,x.getzzn()); copy(fn.b,y.getzzn()); copy(fn.c,z.getzzn());}
void ZZn2::get(ZZn& x,ZZn& y) const
{{copy(fn.a,x.getzzn()); copy(fn.b,y.getzzn()); }}
Ps_ZZn operator*(Ps_ZZn& a,Ps_ZZn& b)
{
Ps_ZZn prod;
ZZn t;
term_ps_zzn *aptr,*bptr,*pos;
int ka,kb,i,pa,pb,d,deg,g;
if (a.IsInt())
{
if (a.start==NULL) return prod;
else return (a.start->an*b);
}
if (b.IsInt())
{
if (b.start==NULL) return prod;
else return (b.start->an*a);
}
g=igcd(a.pwr,b.pwr);
deg=psN/g;
#ifdef FFT
if (deg>=FFT_BREAK_EVEN)
{ // use fast methods
big *A,*B,*C;
A=(big *)mr_alloc(deg,sizeof(big));
B=(big *)mr_alloc(deg,sizeof(big));
C=(big *)mr_alloc(deg,sizeof(big));
char *memc=(char *)memalloc(deg);
for (i=0;i<deg;i++) C[i]=mirvar_mem(memc,i);
ka=a.pwr/g;
a.decompress(ka);
aptr=a.start;
while (aptr!=NULL)
{
d=aptr->n;
if (d >= deg) break;
A[d]=getbig(aptr->an);
aptr=aptr->next;
}
kb=b.pwr/g;
b.decompress(kb);
bptr=b.start;
while (bptr!=NULL)
{
d=bptr->n;
if (d >= deg) break;
B[d]=getbig(bptr->an);
bptr=bptr->next;
}
mr_ps_zzn_mul(deg,A,B,C);
pos=NULL;
for (d=0;d<deg;d++)
{
t=C[d];
if (t.iszero()) continue;
pos=prod.addterm(t,d*g,pos);
}
memkill(memc,deg);
a.compress(ka); b.compress(kb);
mr_free(C); mr_free(B); mr_free(A);
}
else
{
#endif
bptr=b.start;
while (bptr!=NULL)
{
aptr=a.start;
pb=bptr->n*b.pwr-b.offset;
pos=NULL;
while (aptr!=NULL)
{
pa=aptr->n*a.pwr-a.offset;
if (pb+pa>=psN) break;
pos=prod.addterm(aptr->an*bptr->an,pa+pb,pos);
aptr=aptr->next;
}
bptr=bptr->next;
}
#ifdef FFT
}
#endif
if (prod.start!=NULL) prod.offset=a.offset+b.offset;
return prod;
}
Poly operator*(const Poly& a,const Poly& b)
{
int i,d,dega,degb,deg;
BOOL squaring;
ZZn t;
Poly prod;
term *iptr,*pos;
term *ptr=b.start;
squaring=FALSE;
if (&a==&b) squaring=TRUE;
dega=degree(a);
deg=dega;
if (!squaring)
{
degb=degree(b);
if (degb<dega) deg=degb;
}
else degb=dega;
if (deg>=FFT_BREAK_EVEN) /* deg is minimum - both must be less than FFT_BREAK_EVEN */
{ // use fast methods
big *A,*B,*C;
deg=dega+degb; // degree of product
A=(big *)mr_alloc(dega+1,sizeof(big));
if (!squaring) B=(big *)mr_alloc(degb+1,sizeof(big));
C=(big *)mr_alloc(deg+1,sizeof(big));
for (i=0;i<=deg;i++) C[i]=mirvar(0);
ptr=a.start;
while (ptr!=NULL)
{
A[ptr->n]=getbig(ptr->an);
ptr=ptr->next;
}
if (!squaring)
{
ptr=b.start;
while (ptr!=NULL)
{
B[ptr->n]=getbig(ptr->an);
ptr=ptr->next;
}
mr_poly_mul(dega,A,degb,B,C);
}
else mr_poly_sqr(dega,A,C);
pos=NULL;
for (d=deg;d>=0;d--)
{
t=C[d];
mr_free(C[d]);
if (t.iszero()) continue;
pos=prod.addterm(t,d,pos);
}
mr_free(C);
mr_free(A);
if (!squaring) mr_free(B);
return prod;
}
if (squaring)
{ // squaring
pos=NULL;
while (ptr!=NULL)
{ // diagonal terms
pos=prod.addterm(ptr->an*ptr->an,ptr->n+ptr->n,pos);
ptr=ptr->next;
}
ptr=b.start;
while (ptr!=NULL)
{ // above the diagonal
iptr=ptr->next;
pos=NULL;
while (iptr!=NULL)
{
t=ptr->an*iptr->an;
pos=prod.addterm(t+t,ptr->n+iptr->n,pos);
iptr=iptr->next;
}
ptr=ptr->next;
}
}
else while (ptr!=NULL)
{
pos=NULL;
iptr=a.start;
while (iptr!=NULL)
{
pos=prod.addterm(ptr->an*iptr->an,ptr->n+iptr->n,pos);
iptr=iptr->next;
}
ptr=ptr->next;
}
return prod;
}
