title: How can std::bitset be faster than std::vector<bool>?
body: <p>According to <a href="https://stackoverflow.com/questions/4155847/choosing-between-setint-vs-vectorbool-vs-vectorboolean-t-to-use-as-a-bitm/4155985#4155985">this answer</a> the poster expects a <a href="http://en.cppreference.com/w/cpp/utility/bitset" rel="noreferrer"><code>std::bitset</code></a> of size 100k bits to be faster than a <code>std::vector&lt;bool&gt;</code> when querying individual bits. How can this be possible?</p>
  
  <p>How could they even differ significantly in their implementation, if <code>std::bitset</code> apparently allows for arbitrary sizes just like <code>std::vector</code>?</p>