LRU Cache

Design and implement a data structure for Least Recently Used (LRU) cache. It should support get and put operations.

• get(key): Get the value (which will always be positive) of the key if the key exists in the cache, otherwise return -1.
• put(key, value): Set or insert the value if the key is not already present. When the cache reached its capacity, it should invalidate the least recently used item before inserting a new item.

The cache is initialized with a positive capacity.

Can you do both operations in O(1) time complexity?

Input

• operations: the operations

Output

the return values of get operations

Examples

Example 1:

Input:

1operations = ```
2LRUCache 2
3put 1 1
4put 2 2
5get 1
6put 3 3
7get 2
8put 4 4
9get 1
10get 3
11get 4

1
2**Output**: ````
31
4-1
5-1
63
74

`

Explanation:

See input.

Try it yourself

Solution