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    LRU Cache

    Medium

    Problem Description

    Design a data structure that follows the constraints of a Least Recently Used (LRU) cache.

    Support:

    • get(key): return value if key exists, otherwise -1.
    • put(key, value): insert/update key and evict the least recently used key when capacity is exceeded.

    In this live problem, operations are simulated and your method should return outputs where:

    • get returns an integer.
    • put returns null.

    Example

    capacity = 2
operations = ["put","put","get","put","get","put","get","get","get"]
values = [[1,1],[2,2],[1],[3,3],[2],[4,4],[1],[3],[4]]

Output: [null,null,1,null,-1,null,-1,3,4]

    Constraints

    • 1 <= capacity <= 3000
    • Up to 2 * 10^5 total operations in real interview settings.

    Follow-up

    Can you achieve O(1) average time for both get and put?

    Solution

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