/*
* inclusive partial sum (i.e. up to element i included)
*/
uint64_t psum(uint64_t i) const {
assert(i<size_);
i++;
uint64_t s = 0;
uint64_t pos = 0;
// optimization for bitvectors
for(uint64_t j = 0;j<(i/64)*(width_==1);++j){
s += __builtin_popcountll(words[j]);
pos += 64;
}
s += width_>1 or i%64==0 ?
0 :
__builtin_popcountll( words[i/64] & ((ulint(1) << (i%64))-1) );
// end optimization for bitvectors
for(uint64_t j=pos;j<i*(width_>1);++j){
s += at(j);
}
return s;
}
/*
* return alphabet, INCLUDED BWT terminator
*/
set<char_type> get_alphabet(){
set<char_type> A(alphabet);
A.insert(ulint(TERMINATOR));
return A;
}
