146_LRU_cache.py

class LRUCache:

    def __init__(self, capacity: int):
        self.capacity = capacity
        self.cache = {}
        self.queue = []

    def get(self, key: int) -> int:
        if key in self.cache:
            self.update_queue(key)
            return self.cache[key]
        else:
            return -1

    def put(self, key: int, value: int) -> None:
        if key in self.cache:
            self.update_queue(key)
            self.cache[key] = value
        else:
            if len(self.queue) == self.capacity:
                tmp = self.queue.pop()
                self.queue.insert(0, key)
                self.cache.pop(tmp)
                self.cache[key] = value
            else:
                self.cache[key] = value
                self.queue.insert(0, key)

    def update_queue(self, key: int):
        self.queue.remove(key)
        self.queue.insert(0, key)


# Your LRUCache object will be instantiated and called as such:
# obj = LRUCache(capacity)
# param_1 = obj.get(key)
# obj.put(key,value)

'''
    This is my personal record of solving Leetcode Problems. 
    If you have any questions, please discuss them in [Issues](https://github.com/mengxinayan/leetcode/issues).
    Copyright (C) 2020-2022  mengxinayan

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
'''