def test_moveToHead(self):
l = DoublyLinkedList()
sanity = []
for i in xrange(8):
if i % 2 == 0:
l.addToHead(i)
sanity = [i] + sanity
else:
l.addToTail(i)
sanity.append(i)
self.assertEqual(list(l), sanity)
original_dll = l.copy()
original_sanity = sanity[::]
for j in xrange(i):
#Move each item to the head once
l.moveToHead(l.getNodeByIndex(j))
list_move_to_head(sanity, j)
try:
self.assertEqual(list(l), sanity)
except:
import code
code.interact(local=locals())
l = original_dll
sanity = original_sanity
l = DoublyLinkedList()
sanity = []
for i in xrange(8):
if i % 2 == 1:
l.addToHead(i)
sanity = [i] + sanity
else:
l.addToTail(i)
sanity.append(i)
self.assertEqual(list(l), sanity)
original_dll = l.copy()
original_sanity = sanity[::]
for j in xrange(i):
#Move each item to the head once
l.moveToHead(l.getNodeByIndex(j))
list_move_to_head(sanity, j)
self.assertEqual(list(l), sanity)
l = original_dll
sanity = original_sanity
def test_moveToHead(self): l = DoublyLinkedList() sanity = [] for i in xrange(8): if i % 2 == 0: l.addToHead(i) sanity = [i] + sanity else: l.addToTail(i) sanity.append(i) self.assertEqual(list(l), sanity) original_dll = l.copy() original_sanity = sanity[::] for j in xrange(i): #Move each item to the head once l.moveToHead(l.getNodeByIndex(j)) list_move_to_head(sanity, j) try: self.assertEqual(list(l), sanity) except: import code; code.interact(local=locals()) l = original_dll sanity = original_sanity l = DoublyLinkedList() sanity = [] for i in xrange(8): if i % 2 == 1: l.addToHead(i) sanity = [i] + sanity else: l.addToTail(i) sanity.append(i) self.assertEqual(list(l), sanity) original_dll = l.copy() original_sanity = sanity[::] for j in xrange(i): #Move each item to the head once l.moveToHead(l.getNodeByIndex(j)) list_move_to_head(sanity, j) self.assertEqual(list(l), sanity) l = original_dll sanity = original_sanity
def test_AddToHead_and_addToTail(self):
l = DoublyLinkedList()
sanity = []
for i in xrange(8):
if i % 2 == 0:
l.addToHead(i)
sanity = [i] + sanity
else:
l.addToTail(i)
sanity.append(i)
self.assertEqual(list(l), sanity)
l = DoublyLinkedList()
sanity = []
for i in xrange(8):
if i % 2 == 1:
l.addToHead(i)
sanity = [i] + sanity
else:
l.addToTail(i)
sanity.append(i)
self.assertEqual(list(l), sanity)
def test_AddToHead_and_addToTail(self): l = DoublyLinkedList() sanity = [] for i in xrange(8): if i % 2 == 0: l.addToHead(i) sanity = [i] + sanity else: l.addToTail(i) sanity.append(i) self.assertEqual(list(l), sanity) l = DoublyLinkedList() sanity = [] for i in xrange(8): if i % 2 == 1: l.addToHead(i) sanity = [i] + sanity else: l.addToTail(i) sanity.append(i) self.assertEqual(list(l), sanity)
def test_addToHead(self):
l = DoublyLinkedList()
for i in xrange(4):
self.assertIs(l.size, i)
l.addToHead(i)
self.assertEqual(list(l), range(i, -1, -1))
class LruCacher(object):
def __init__(self, max_size, plan_b_func):
"max_size: the largest number of items the cache can have."
"plan_b_func: the function that will be called with the query as its"
" argument if a query isn't cached. The result will then"
" be associated with the query."
if max_size < 0:
raise ValueError("max_size must be positive.")
if not callable(plan_b_func):
raise TypeError("plan_b_func must be callable.")
self.max_size = max_size
self.ht = {}
self.ll = DoublyLinkedList()
self.plan_b_func = plan_b_func
def lookup(self, query):
"Perform a query on the cache. The elements of the cache are "
"automatically adjusted. If the query is in the cache, move it to the "
"front of the linked list then return it. If it's not in the cache, "
"remove the last query in the linked list, queries the plan_b_func for"
"the result, adds it to the cache, and returns it. This should be a "
"decorator."
"Cached items have their queries as keys in the hashtable, which point"
"to elements in a doubly linked list. Linked lsit nodes have two "
"attributesdata: data, which is the result of calling plan_b_func, and"
"and query, which is the query itself."
found_in_cache = None
if query not in self.ht:
found_in_cache = False
result = self.plan_b_func(query)
if len(self.ht) == self.max_size and self.max_size is not 0:
if self.ll.tail is not None:
del self.ht[self.ll.tail.query]
self.ll.removeTail()
if self.max_size != 0:
self.ll.addToHead(result)
self.ll.head.query = query
self.ht[query] = self.ll.head
else:
#The query was in the cache. Move it to the front of
#the linked list.
found_in_cache = True
node = self.ht[query]
result = node.data
return result, found_in_cache
def update(self, query, val):
"Update the value stored in the cache pointed to by query. If query "
"isn't cached, nothing happens."
if query not in self.ht:
return
node = self.ht[query]
node.data = val
def size(self):
return len(self.ht)
def test_addToHead(self): l = DoublyLinkedList() for i in xrange(4): self.assertIs(l.size, i) l.addToHead(i) self.assertEqual(list(l), range(i, -1, -1))
class LruCacher(object):
def __init__(self, max_size, plan_b_func):
"max_size: the largest number of items the cache can have."
"plan_b_func: the function that will be called with the query as its"
" argument if a query isn't cached. The result will then"
" be associated with the query."
if max_size < 0:
raise ValueError("max_size must be positive.")
if not callable(plan_b_func):
raise TypeError("plan_b_func must be callable.")
self.max_size = max_size
self.ht = {}
self.ll = DoublyLinkedList()
self.plan_b_func = plan_b_func
def lookup(self, query):
"Perform a query on the cache. The elements of the cache are "
"automatically adjusted. If the query is in the cache, move it to the "
"front of the linked list then return it. If it's not in the cache, "
"remove the last query in the linked list, queries the plan_b_func for"
"the result, adds it to the cache, and returns it. This should be a "
"decorator."
"Cached items have their queries as keys in the hashtable, which point"
"to elements in a doubly linked list. Linked lsit nodes have two "
"attributesdata: data, which is the result of calling plan_b_func, and"
"and query, which is the query itself."
found_in_cache = None
if query not in self.ht:
found_in_cache = False
result = self.plan_b_func(query)
if len(self.ht) == self.max_size and self.max_size is not 0:
if self.ll.tail is not None:
del self.ht[self.ll.tail.query]
self.ll.removeTail()
if self.max_size != 0:
self.ll.addToHead(result)
self.ll.head.query = query
self.ht[query] = self.ll.head
else:
#The query was in the cache. Move it to the front of
#the linked list.
found_in_cache = True
node = self.ht[query]
result = node.data
return result, found_in_cache
def update(self, query, val):
"Update the value stored in the cache pointed to by query. If query "
"isn't cached, nothing happens."
if query not in self.ht:
return
node = self.ht[query]
node.data = val
def size(self):
return len(self.ht)
