3 ms·

If it's not constant time on both ends, it's not a deque. You can already insert items at any index in an array with linear cost.

• sgtnoodle 4y ago
  I invite you to think about the problem for a while, and try to think of a way to implement a performant deque on top of a resize-able array. I promise you it's possible.
  • eru 4y ago
    I don't think the comment you replied to disagreed with that.