📅  最后修改于: 2022-03-11 14:52:26.990000             🧑  作者: Mango
On the other hand, a HashMap has an average time complexity of O(1)
for put() , contains() and remove() operations.
The worst-case time complexity for those operations is O(log n)
since Java 8, and O(n) before that. Space-complexity wise, both
have a complexity of O(n)