def test_remove_4():
l = DoubleLinkedList()
l.append(5)
l.remove(l.front)
assert l.front is None
assert l.end is None
assert_contains(l, [])
def test_remove_6():
l = DoubleLinkedList()
l.append(5)
l.append(7)
l.remove(l.end)
assert l.front.value == 5
assert l.end is not None
assert_contains(l, [5])
def test_remove_3():
l = DoubleLinkedList()
l.append(5)
l.append(7)
l.append(9)
l.remove(l.front)
assert l.front.value == 7
assert l.end.value == 9
assert_contains(l, [7, 9])
def test_remove_2():
l = DoubleLinkedList()
l.append(5)
l.append(7)
l.append(9)
l.remove(l.end)
assert l.front.value == 5
assert l.end.value == 7
assert_contains(l, [5, 7])
def test_remove():
l = DoubleLinkedList()
l.append(5)
l.append(7)
l.append(9)
l.remove(l.front.next)
assert l.front.value == 5
assert l.front.next.value == 9
assert_contains(l, [5, 9])
class LRUCache:
class Node:
def __init__(self, value, access_ref):
self.value = value
self.access_ref = access_ref
def __init__(self, max_size):
self.max_size = max_size
self.cache = {}
self.accesses = DoubleLinkedList()
def set(self, key, value):
self._evict()
if key in self.cache:
list_ref = self.cache[key].access_ref
self.accesses.remove(list_ref)
self.accesses._append(list_ref)
else:
list_ref = self.accesses.append(key)
self.cache[key] = LRUCache.Node(value, list_ref)
def get(self, key):
if key not in self.cache:
raise ValueError('{} not found in cache'.format(key))
list_ref = self.cache[key].access_ref
self.accesses.remove(list_ref)
self.accesses._append(list_ref)
return self.cache[key].value
def _evict(self):
if self.max_size == len(self.cache):
node = self.accesses.front
self.accesses.remove(node)
del self.cache[node.value]