> I'll bite: in arrays, front deletion (like back deletion) can be done in O(1) time. Keep a pointer to the first element, and just increment it upon front dele

> I'll bite: in arrays, front deletion (like back deletion) can be done in O(1) time. Keep a pointer to the first element, and just increment it upon front deletion (and free the element if necessary). Obviously, you may want to be smart to avoid memory use getting out of hand. Actually that's how they often do array-based queues and deques. To help with memory use they let the tail pointer overflow through the end (so you could have tail at index 2 and head at index 8).