3 ms·

but isn't find() an O(n) operation already?

• int_19h 8y ago
  Indeed! Which is why find() is not a member function on vector (so my snippet above is wrong - I just missed that part). It's a global function, so you need to do: if (find(x, v.begin(), v.end()) != v.end()) ... For maps and sets, find is a member function though. Same principle - if it is implemented in some optimized way, the class provides it directly, but not otherwise.