Memcache

这里注意ttl等于0的kv对一直存在就行

from collections import namedtuple

class KVpair:
    def __init__(self, start, value, ttl):
        self.start = start
        self.value = value
        self.ttl = ttl

class Memcache:

    def __init__(self):
        # initialize your data structure here.
        self.store = {}
        self.invalidNum = 2 ** 31 - 1

    # @param {int} curtTime an integer
    # @param {int} key an integer
    # @return an integer
    def get(self, curtTime, key):
        # Write your code here
        tmp = self.store.get(key, -1)
        if tmp != -1:
            endTime = tmp.start + tmp.ttl - 1
            if tmp.ttl != 0 and endTime < curtTime:
                self.store.pop(key)
                return self.invalidNum
            return tmp.value
        return self.invalidNum

    # @param {int} curtTime an integer
    # @param {int} key an integer
    # @param {int} value an integer
    # @param {int} ttl an integer
    # @return nothing
    def set(self, curtTime, key, value, ttl):
        # Write your code here
        self.store[key] = KVpair(curtTime, value, ttl)

    # @param {int} curtTime an integer
    # @param {int} key an integer
    # @return nothing
    def delete(self, curtTime, key):
        # Write your code here
        if key in self.store:
            self.store.pop(key)

    # @param {int} curtTime an integer
    # @param {int} key an integer
    # @param {int} delta an integer
    # @return an integer
    def incr(self, curtTime, key, delta):
        # Write your code here
        if key in self.store:
            self.store[key].value += delta
            return self.store[key].value
        return self.invalidNum

    # @param {int} curtTime an integer
    # @param {int} key an integer
    # @param {int} delta an integer
    # @return an integer
    def decr(self, curtTime, key, delta):
        # Write your code here
        if key in self.store:
            self.store[key].value -= delta
            return self.store[key].value
        return self.invalidNum