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greatzues

#1 Created at ... [Delete] [Delete and Lock User]

不太明白下面这句的意思 :smile:

containsKey = 1 if key in self else 0

我的理解是传入的key若已存在，containsKey为1，若不存在，则containsKey为0

从而下面的判断：

if len(self)-containsKey >= self._capacity:

当前字典长度减去containskey若大于或等于字典容量，移除第一个key。

if containsKey:

我测了下，当containskey为0时，即key不存在时，不执行此判断，因此仅在containskey为1时，删去同样的键值，最后再继承父类方法添加同样的进去。

OrderedDict.__setitem__(self, key, value)

因为先删去了同名的key再新增，所以新增的同名key，会改变原同名key的顺序

greatzues

#2 Created at ... [Delete] [Delete and Lock User]

推演过程如下：

>>> A = LastUpdatedOrderedDict(3)
>>> A['one'] = 1
add: ('one', 1)
>>> A['two'] = 2
add: ('two', 2)
>>> A['three'] = 3
add: ('three', 3)
>>> A['one'] = 11
set: ('one', 11)
>>> A['four'] = 4
remove: ('two', 2)
add: ('four', 4)
>>> A
LastUpdatedOrderedDict([('three', 3), ('one', 11), ('four', 4)])
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