c++ - bit vector intersect in handling parquet file format -

i handling parquet file format. example:

a group of data:

1 2 null 3 4 5 6 null 7 8 null null 9 10 11 12 13 14

i got bit vector indicate null element:

1 1 0 1 1 1 1 0 1 1 0 0 1 1 1 1 1 1

and store non-null element:

1 2 3 4 5 6 7 8 9 10 11 12 13 14

i want evaluate predicate: big 5

i compared non-null element 5 , got bit vector:

0 0 0 0 0 1 1 1 1 1 1 1 1 1

i want got bit vector elements:

0 0 0 0 0 0 1 0 1 1 0 0 1 1 1 1 1 1

the 0 in bold null elements, should false.

void intersectbitvec(vector<int64_t>& bit_vec, vector<int64_t>& sub_bit_vec) { int data_idx = 0, int bit_idx = 63; (int = 0; < bit_vec.size(); ++i) {   (int j = 63; j >=0; --j) {     if (bit_vec[i] & 0x01 << j) {       if (!(sub_bit_vec[data_idx] & 0x01 << bit_idx)) {         bit_vec[i] &= ~(0x01 << j);       }       if (--bit_idx < 0) {         --data_idx;         bit_idx = 63;       }     }   } }} 

my code quite ugly, there anyway make fast? great thanks!