Hi Folks, Having gotten a big chunk of code to work, I'm now spending a few days making it fast. So far, I've removed enough overhead to drop our runtime by a factor of 4, and a big part of that was replacing some other data structures with dynamic_bitset. Profiling data now indicates that one of the more expensive operations is spending most of its time calling dynamic_bitset<>::test a bajillion times. My question is this: is dynamic_bitset::test generally thought to be the fastest way to access a specific bit in a dynamic_bitset? Are there other ways to determine if bit n is set? (I assume that anything using dynamic_bitset::operator[] will be slower, since it has to set up a proxy, but have not tested this.) Any thoughts are appreciated. Thanks! -- Dave Steffen, Ph.D. Disobey this command! Software Engineer IV - Douglas Hofstadter Numerica Corporation dg@steffen a@t numerica d@ot us (remove @'s to email me)