static void eval(Thread& thread, A const& a, Integer const& d, int64_t nonzero, Value& out)
{
A r(nonzero);
int64_t j = 0;
typename A::Element const* ae = a.v();
typename Integer::Element const* de = d.v();
typename A::Element* re = r.v();
int64_t length = d.length();
for(int64_t i = 0; i < length; i++) {
if(Integer::isNA(de[i])) re[j++] = A::NAelement;
else if(de[i] != 0) re[j++] = ae[de[i]-1];
}
out = r;
}
static void eval(Thread& thread, A const& a, Integer const& d, int64_t nonzero, Value& out)
{
std::set<Integer::Element> index;
typename A::Element const* ae = a.v();
typename Integer::Element const* de = d.v();
int64_t length = d.length();
for(int64_t i = 0; i < length; i++) if(-de[i] > 0 && -de[i] <= (int64_t)a.length()) index.insert(-de[i]);
// iterate through excluded elements copying intervening ranges.
A r(a.length()-index.size());
typename A::Element* re = r.v();
int64_t start = 1;
int64_t k = 0;
for(std::set<Integer::Element>::const_iterator i = index.begin(); i != index.end(); ++i) {
int64_t end = *i;
for(int64_t j = start; j < end; j++) re[k++] = ae[j-1];
start = end+1;
}
for(int64_t j = start; j <= a.length(); j++) re[k++] = ae[j-1];
out = r;
}
