-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathQueue.py
More file actions
94 lines (94 loc) · 2.79 KB
/
Queue.py
File metadata and controls
94 lines (94 loc) · 2.79 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
class Node(object):
def __init__(self, value=None):
self.value = value
self.next = None
class LinkedNode(object):
def __init__(self, maxsize=None):
self.maxsize = maxsize
self.root = Node()
self.length = 0
self.tailnode = None
def __len__(self):
return self.length
def append(self, value):
if self.maxsize is not None and len(self) > self.maxsize:
raise Exception('full')
node = Node(value)
if self.root.next is None:
self.tailnode = node
self.root.next = self.tailnode
else:
curnode = self.tailnode
curnode.next = node
self.tailnode = node
self.length += 1
def append_left(self, value):
node = Node(value)
headnode = self.root.next
self.root.next = node
node.next = headnode
self.length += 1
def iter_node(self):
curnode = self.root.next
while curnode:
yield curnode
curnode = curnode.next
def __iter__(self):
for node in self.iter_node():
yield node.value
def remove(self, value):
prevnode = self.root
while prevnode:
curnode = prevnode.next
if (curnode is not None) and (curnode.value == value):
prevnode.next = curnode.next
self.length -= 1
return 1
prevnode = prevnode.next
return -1
def popleft(self):
headnode = self.root.next
if headnode is None:
raise Exception('pop from empty LinkedList')
val = headnode.value
self.root.next = headnode.next
self.length -= 1
del headnode
return val
def clear(self):
for node in self.iter_node():
del node
self.root.next = None
self.length = 0
def find(self, value):
index = 0
for node in self.iter_node():
if node.value == value:
return index
index += 1
return -1
class Queue(object):
def __init__(self, maxsize=None):
self.maxsize = maxsize
self._item_linked_list = LinkedNode()
def __len__(self):
return len(self._item_linked_list)
def push(self,value):
if self.maxsize is not None and len(self) > self.maxsize:
raise Exception('full')
return self._item_linked_list.append(value)
def pop(self):
if len(self) == 0:
raise Exception('queue empty')
return self._item_linked_list.popleft()
def test_queue():
q = Queue()
for i in range(3):
q.push(i)
assert q.pop() == 0
assert q.pop() == 1
assert q.pop() == 2
assert len(q) == 0
print("successful")
if __name__ == "__main__":
test_queue()