However, keep in mind that a) it doesn't resize the bitset: it's your responsibility to ensure that you won't copy "too many blocks" into it
Now, I am writing num_blocks()-1 blocks, and treat the last block separately. I think I can just use bit sizes that are multiples of block size, although the last few bits will not be used. In this way, the algorithm will be cleaner and faster, and boost/dynamic_bitset will not complain.
2. retrieve succ from each column of this matrix. Curently, I am doing something like
vector<int> succ(4); .... for(size_t i=0; i<4; ++i) succ[i] = succ_matrix[i][cur]; // process succ cur ++ // get another row
I'm confused by this. Does succ_matrix[i][cur] yields a bool or an int? And in the latter case, what value does it actually return?
I was using dynamic_bitset to get results (succ) but the performance was bad. vector<int> is much faster. I can afford to use int since succ is usually small.
The reason why dynamic_bitset does not expose block-level iterators is that I see blocks as an implementation detail. I'm not even convinced there should be a template parameter for them.
I have checked my random number generator. It will produce full range of integer values (0 - 2^32-1). As a result, I use unsigned long as the template parameter of dynamic_bitset. At least for my usage, this template parameter is useful.
*Nonetheless* incrementing/decrementing iterators still requires some computation. Maybe you are thinking that such iterators could be implemented by storing a pointer or reference to a bitset and an index, but would not be conforming.
You mean *(++ptr) will be as slow as succ[++idx]? I would be really disappointed. Bo