title: Performance differences between std::count and std::find
body: <p>This might be a stupid question but I want to check a container (in this case an <code>std::vector</code> of <code>bool</code> but a broader approach would be better) to check if a value exist. As I understand both the run time <code>std::count</code> and <code>std::find</code> are linear and count might slower if the item is in the range but I think that both should be the same if the object exists, but I could see the probability that a complier could vectorize <code>std::count</code> and <strong>therefore</strong> making <code>std::count</code> run faster. Am I correct with the first assumption that both will run the same or is the second assumption that compliers can <strong>vectorize <code>std::count</code></strong> true?  </p>