前言

距放弃C++已经过去整整一年
这一年我学习了Python的基础语法，以及现在的Python数据结构
从时间上来看，我的学习成果也太少啦。没错，各种尝试，各种摆烂，主要的成果只有上述两个
最后的一学年，即将到来的实习…
先把现有的成果存起来吧，等学完数据结构，就开始日常的算法刷题，补上我鸽了无限时间的各个项目
OneSync Lite、OneSync、OneShare等等



Array

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class Array():
    def __init__(self, size=32):
        self._size = size
        self._items = [None] * size

    def __getitem__(self, index):
        return self._items[index]

    def __setitem__(self, index, value):
        self._items[index] = value

    def __len__(self):
        return self._size

    def clear(self, value=None):
        self._items = [value] * len(self._items)

    def __iter__(self):
        for item in self._items:
            yield item


def test():
    size = 10
    a = Array(size)
    a[0] = 1
    assert a[0] == 1

    a.clear()
    assert a[0] is None


test()



LinkedList

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class Node():
    def __init__(self, value=None, next=None):
        self.value, self.next = value, next


class LinkedList():
    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)
        tailnode = self.tailnode
        if tailnode is None:
            self.root.next = node
        else:
            tailnode.next = node
        self.tailnode = node
        self.length += 1

    def appendleft(self, value):
        if self.maxsize is not None and len(self) >= self.maxsize:
            raise Exception('Full')
        headnode = self.root.next
        node = Node(value)
        self.root.next = node
        node.next = headnode
        if self.tailnode is None:
            self.tailnode = node
        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
        curnode = self.root.next
        while curnode is not None:
            if curnode.value == value:
                prevnode.next = curnode.next
                if curnode is self.tailnode:
                    if prevnode is self.root:
                        self.tailnode = None
                    else:
                        self.tailnode = prevnode
                del curnode
                self.length -= 1
                return
            prevnode = curnode
            curnode = curnode.next

    def find(self, value):
        index = 0
        for node in self.iter_node():
            if node.value == value:
                return index
            index += 1
        return -1

    def popleft(self):
        if self.root.next is None:
            raise Exception('empty')
        headnode = self.root.next
        self.root.next = headnode.next
        self.length -= 1
        value = headnode.value
        del headnode
        return value

    def clear(self):
        for node in self.iter_node():
            del node
        self.root.next = None
        self.length = 0


def test():
    ll = LinkedList()

    ll.append(0)
    ll.append(1)
    ll.append(2)

    assert len(ll) == 3
    assert ll.find(2) == 2
    assert ll.find(3) == -1

    ll.remove(0)
    assert len(ll) == 2
    assert ll.find(0) == -1

    assert list(ll) == [1, 2]

    ll.appendleft(0)
    assert list(ll) == [0, 1, 2]
    assert len(ll) == 3

    headvalue = ll.popleft()
    assert headvalue == 0
    assert len(ll) == 2
    assert list(ll) == [1, 2]

    ll.clear()
    assert len(ll) == 0


test()



CircularLinkedList

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class Node():
    def __init__(self, value=None, prev=None, next=None):
        self.value, self.prev, self.next = value, prev, next


class CircularDoublyLinkedList():
    def __init__(self, maxsize=None):
        self.maxsize = maxsize
        node = Node()
        node.next, node.prev = node, node
        self.root = node
        self.length = 0  # 增删操作时注意更新

    def __len__(self):
        return self.length

    def headnode(self):  # 增删操作时注意更新
        return self.root.next

    def tailnode(self):  # 增删操作时注意更新
        return self.root.prev

    def append(self, value):
        if self.maxsize is not None and len(self) >= self.maxsize:
            raise Exception('full')
        node = Node(value=value)
        tailnode = self.tailnode()

        tailnode.next = node
        node.prev = tailnode
        node.next = self.root
        self.root.prev = node

        self.length += 1

    def appendleft(self, value):
        if self.maxsize is not None and len(self) >= self.maxsize:
            raise Exception('full')
        node = Node(value=value)

        if self.root.next is self.root:
            node.next = self.root
            node.prev = self.root
            self.root.next = node
            self.root.prev = node
        else:
            node.prev = self.root
            headnode = self.root.next
            node.next = headnode
            headnode.prev = node
            self.root.next = node
        self.length += 1

    def remove(self, node):
        if node is self.root:
            return
        else:
            node.prev.next = node.next
            node.next.prev = node.prev
            del node
        self.length -= 1

    def insert(self, key, value):
        if self.maxsize is not None and len(self) >= self.maxsize:
            raise Exception('full')

        node = Node(value=value)
        inserted = False
        for curnode in self.iter_node():
            if key == curnode.value:
                node.prev = curnode
                node.next = curnode.next
                curnode.next.prev = node
                curnode.next = node
                inserted = True
                break  # 找到了匹配的节点并插入后，就可以退出循环了

        if not inserted:  # 如果没有插入节点（也就是没找到匹配的 key），则添加到链表的末尾
            tailnode = self.tailnode()
            node.prev = tailnode
            node.next = self.root
            tailnode.next = node
            self.root.prev = node

        self.length += 1

    def iter_node(self):
        if self.root.next is self.root:
            return
        curnode = self.root.next
        while curnode.next is not self.root:
            yield curnode
            curnode = curnode.next
        yield curnode

    def __iter__(self):
        for node in self.iter_node():
            yield node.value

    def iter_node_reverse(self):
        if self.root.prev is self.root:
            return
        curnode = self.root.prev
        while curnode.prev is not self.root:
            yield curnode
            curnode = curnode.prev
        yield curnode


def test():
    dll = CircularDoublyLinkedList()
    assert len(dll) == 0

    dll.append(0)
    dll.append(1)
    dll.append(2)

    assert list(dll) == [0, 1, 2]

    assert [node.value for node in dll.iter_node()] == [0, 1, 2]
    assert [node.value for node in dll.iter_node_reverse()] == [2, 1, 0]

    headnode = dll.headnode()
    assert headnode.value == 0
    dll.remove(headnode)
    assert len(dll) == 2
    assert [node.value for node in dll.iter_node()] == [1, 2]

    dll.appendleft(0)
    assert [node.value for node in dll.iter_node()] == [0, 1, 2]


test()



Queue

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class Node():
    def __init__(self, value=None, next=None):
        self.value, self.next = value, next


class LinkedList():
    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)
        tailnode = self.tailnode
        if tailnode is None:
            self.root.next = node
        else:
            tailnode.next = node
        self.tailnode = node
        self.length += 1

    def appendleft(self, value):
        if self.maxsize is not None and len(self) >= self.maxsize:
            raise Exception('Full')
        headnode = self.root.next
        node = Node(value)
        self.root.next = node
        node.next = headnode
        if self.tailnode is None:
            self.tailnode = node
        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
        curnode = self.root.next
        while curnode is not None:
            if curnode.value == value:
                prevnode.next = curnode.next
                if curnode is self.tailnode:
                    if prevnode is self.root:
                        self.tailnode = None
                    else:
                        self.tailnode = prevnode
                del curnode
                self.length -= 1
                return
            prevnode = curnode
            curnode = curnode.next

    def find(self, value):
        index = 0
        for node in self.iter_node():
            if node.value == value:
                return index
            index += 1
        return -1

    def popleft(self):
        if self.root.next is None:
            raise Exception('empty')
        headnode = self.root.next
        self.root.next = headnode.next
        self.length -= 1
        value = headnode.value
        del headnode
        return value

    def clear(self):
        for node in self.iter_node():
            del node
        self.root.next = None
        self.length = 0


class FullError(Exception):
    pass


class EmptyError(Exception):
    pass


class Queue():
    def __init__(self, maxsize=None):
        self.maxsize = maxsize
        self._item_linked_list = LinkedList()

    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 FullError('full')
        return self._item_linked_list.append(value)

    def pop(self):
        if len(self) <= 0:
            raise EmptyError('empty')
        return self._item_linked_list.popleft()


def test():
    import pytest
    q = Queue()
    q.push(0)
    q.push(1)
    q.push(2)

    assert len(q) == 3

    assert q.pop() == 0
    assert q.pop() == 1
    assert q.pop() == 2

    with pytest.raises(EmptyError) as excinfo:
        q.pop()
    assert 'empty' in str(excinfo.value)



ArrayQueue

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class Array():
    def __init__(self, size=32):
        self._size = size
        self._items = [None] * size

    def __getitem__(self, index):
        return self._items[index]

    def __setitem__(self, index, value):
        self._items[index] = value

    def __len__(self):
        return self._size

    def clear(self, value=None):
        self._items = [value] * len(self._items)

    def __iter__(self):
        for item in self._items:
            yield item


class FullError(Exception):
    pass


class EmptyError(Exception):
    pass


class ArrayQueue():
    def __init__(self, maxsize):
        self.maxsize = maxsize
        self.array = Array(maxsize)
        self.head = 0
        self.tail = 0

    def push(self, value):
        if len(self) >= self.maxsize:
            raise FullError('full')
        self.array[self.head % self.maxsize] = value
        self.head += 1

    def pop(self):
        if len(self) <= 0:
            raise EmptyError('empty')
        value = self.array[self.tail % self.maxsize]
        self.tail += 1
        return value

    def __len__(self):
        return self.head - self.tail


def test():
    import pytest
    size = 5
    q = ArrayQueue(size)
    for i in range(size):
        q.push(i)

    with pytest.raises(FullError) as excinfo:
        q.push(size)
    assert 'full' in str(excinfo.value)

    assert len(q) == size

    assert q.pop() == 0
    assert q.pop() == 1

    q.push(5)
    assert len(q) == 4

    assert q.pop() == 2
    assert q.pop() == 3
    assert q.pop() == 4
    assert q.pop() == 5

    assert len(q) == 0



Deque

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class Node():
    def __init__(self, value=None, prev=None, next=None):
        self.value, self.prev, self.next = value, prev, next


class CircularDoublyLinkedList():
    def __init__(self, maxsize=None):
        self.maxsize = maxsize
        node = Node()
        node.next, node.prev = node, node
        self.root = node
        self.length = 0  # 增删操作时注意更新

    def __len__(self):
        return self.length

    def headnode(self):  # 增删操作时注意更新
        return self.root.next

    def tailnode(self):  # 增删操作时注意更新
        return self.root.prev

    def append(self, value):
        if self.maxsize is not None and len(self) >= self.maxsize:
            raise Exception('full')
        node = Node(value=value)
        tailnode = self.tailnode()

        tailnode.next = node
        node.prev = tailnode
        node.next = self.root
        self.root.prev = node

        self.length += 1

    def appendleft(self, value):
        if self.maxsize is not None and len(self) >= self.maxsize:
            raise Exception('full')
        node = Node(value=value)

        if self.root.next is self.root:
            node.next = self.root
            node.prev = self.root
            self.root.next = node
            self.root.prev = node
        else:
            node.prev = self.root
            headnode = self.root.next
            node.next = headnode
            headnode.prev = node
            self.root.next = node
        self.length += 1

    def remove(self, node):
        if node is self.root:
            return
        else:
            node.prev.next = node.next
            node.next.prev = node.prev
            del node
        self.length -= 1

    def insert(self, key, value):
        if self.maxsize is not None and len(self) >= self.maxsize:
            raise Exception('full')

        node = Node(value=value)
        inserted = False
        for curnode in self.iter_node():
            if key == curnode.value:
                node.prev = curnode
                node.next = curnode.next
                curnode.next.prev = node
                curnode.next = node
                inserted = True
                break  # 找到了匹配的节点并插入后，就可以退出循环了

        if not inserted:  # 如果没有插入节点（也就是没找到匹配的 key），则添加到链表的末尾
            tailnode = self.tailnode()
            node.prev = tailnode
            node.next = self.root
            tailnode.next = node
            self.root.prev = node

        self.length += 1

    def iter_node(self):
        if self.root.next is self.root:
            return
        curnode = self.root.next
        while curnode.next is not self.root:
            yield curnode
            curnode = curnode.next
        yield curnode

    def __iter__(self):
        for node in self.iter_node():
            yield node.value

    def iter_node_reverse(self):
        if self.root.prev is self.root:
            return
        curnode = self.root.prev
        while curnode.prev is not self.root:
            yield curnode
            curnode = curnode.prev
        yield curnode


class Deque(CircularDoublyLinkedList):

    def pop(self):
        if len(self) == 0:
            raise Exception('empty')
        tailnode = self.tailnode()
        value = tailnode.value
        self.remove(tailnode)
        return value

    def popleft(self):
        if len(self) == 0:
            raise Exception('empty')
        headnode = self.headnode()
        value = headnode.value
        self.remove(headnode)
        return value



Stack

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class Node():
    def __init__(self, value=None, prev=None, next=None):
        self.value, self.prev, self.next = value, prev, next


class CircularDoublyLinkedList():
    def __init__(self, maxsize=None):
        self.maxsize = maxsize
        node = Node()
        node.next, node.prev = node, node
        self.root = node
        self.length = 0  # 增删操作时注意更新

    def __len__(self):
        return self.length

    def headnode(self):  # 增删操作时注意更新
        return self.root.next

    def tailnode(self):  # 增删操作时注意更新
        return self.root.prev

    def append(self, value):
        if self.maxsize is not None and len(self) >= self.maxsize:
            raise Exception('full')
        node = Node(value=value)
        tailnode = self.tailnode()

        tailnode.next = node
        node.prev = tailnode
        node.next = self.root
        self.root.prev = node

        self.length += 1

    def appendleft(self, value):
        if self.maxsize is not None and len(self) >= self.maxsize:
            raise Exception('full')
        node = Node(value=value)

        if self.root.next is self.root:
            node.next = self.root
            node.prev = self.root
            self.root.next = node
            self.root.prev = node
        else:
            node.prev = self.root
            headnode = self.root.next
            node.next = headnode
            headnode.prev = node
            self.root.next = node
        self.length += 1

    def remove(self, node):
        if node is self.root:
            return
        else:
            node.prev.next = node.next
            node.next.prev = node.prev
            del node
        self.length -= 1

    def insert(self, key, value):
        if self.maxsize is not None and len(self) >= self.maxsize:
            raise Exception('full')

        node = Node(value=value)
        inserted = False
        for curnode in self.iter_node():
            if key == curnode.value:
                node.prev = curnode
                node.next = curnode.next
                curnode.next.prev = node
                curnode.next = node
                inserted = True
                break  # 找到了匹配的节点并插入后，就可以退出循环了

        if not inserted:  # 如果没有插入节点（也就是没找到匹配的 key），则添加到链表的末尾
            tailnode = self.tailnode()
            node.prev = tailnode
            node.next = self.root
            tailnode.next = node
            self.root.prev = node

        self.length += 1

    def iter_node(self):
        if self.root.next is self.root:
            return
        curnode = self.root.next
        while curnode.next is not self.root:
            yield curnode
            curnode = curnode.next
        yield curnode

    def __iter__(self):
        for node in self.iter_node():
            yield node.value

    def iter_node_reverse(self):
        if self.root.prev is self.root:
            return
        curnode = self.root.prev
        while curnode.prev is not self.root:
            yield curnode
            curnode = curnode.prev
        yield curnode


class Deque(CircularDoublyLinkedList):

    def pop(self):
        if len(self) == 0:
            raise Exception('empty')
        tailnode = self.tailnode()
        value = tailnode.value
        self.remove(tailnode)
        return value

    def popleft(self):
        if len(self) == 0:
            raise Exception('empty')
        headnode = self.headnode()
        value = headnode.value
        self.remove(headnode)
        return value


class Stack():
    def __init__(self):
        self.deque = Deque()

    def push(self, value):
        return self.deque.append(value)

    def pop(self):
        return self.deque.pop()

    def __len__(self):
        return len(self.deque)

    def is_empty(self):
        return len(self) == 0


def test():
    import pytest
    s = Stack()
    for i in range(3):
        s.push(i)

    assert len(s) == 3
    assert s.pop() == 2
    assert s.pop() == 1
    assert s.pop() == 0

    assert s.is_empty()

    with pytest.raises(Exception) as excinfo:
        s.pop()
    assert 'empty' in str(excinfo.value)



HashTable

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class Array():
    def __init__(self, size=32, init=None):
        self._size = size
        self._items = [init] * size

    def __getitem__(self, index):
        return self._items[index]

    def __setitem__(self, index, value):
        self._items[index] = value

    def __len__(self):
        return self._size

    def clear(self, value=None):
        self._items = [value] * len(self._items)

    def __iter__(self):
        for item in self._items:
            yield item


class Slot():
    def __init__(self, key, value):
        self.key, self.value = key, value


class HashTable():
    UNUSED = None
    EMPTY = Slot(None, None)

    def __init__(self):
        self._table = Array(8, init=HashTable.UNUSED)
        self.length = 0

    @property
    def _load_factor(self):
        return self.length / float(len(self._table))

    def __len__(self):
        return self.length

    def _hash(self, key):
        return abs(hash(key)) % len(self._table)

    def _find_key(self, key):
        index = self._hash(key)
        _len = len(self._table)
        while self._table[index] is not HashTable.UNUSED:
            if self._table[index] is HashTable.EMPTY:
                index = (index * 5 + 1) % _len
                continue
            elif self._table[index].key == key:
                return index
            else:
                index = (index * 5 + 1) % _len
        return None

    def _slot_can_insert(self, index):
        return (self._table[index] is HashTable.EMPTY or self._table[index] is HashTable.UNUSED)

    def _find_slot_for_insert(self, key):
        index = self._hash(key)
        _len = len(self._table)
        while not self._slot_can_insert(index):
            index = (index * 5 + 1) % _len
        return index

    def __contains__(self, key):
        index = self._find_key(key)
        return index is not None

    def add(self, key, value):
        if key in self:
            index = self._find_key(key)
            self._table[index].value = value
            return False
        else:
            index = self._find_slot_for_insert(key)
            self._table[index] = Slot(key, value)
            self.length += 1
            if self._load_factor >= 0.8:
                self._rehash()
            return True

    def _rehash(self):
        old_table = self._table
        newsize = len(self._table) * 2
        self._table = Array(newsize, HashTable.UNUSED)
        self.length = 0

        for slot in old_table:
            if slot is not HashTable.UNUSED and slot is not HashTable.EMPTY:
                index = self._find_slot_for_insert(slot.key)
                self._table[index] = slot
                self.length += 1

    def get(self, key, default=None):
        index = self._find_key(key)
        if index is None:
            return default
        else:
            return self._table[index].value

    def remove(self, key):
        index = self._find_key(key)
        if index is None:
            raise KeyError()
        value = self._table[index].value
        self.length -= 1
        self._table[index] = HashTable.EMPTY
        return value

    def __iter__(self):
        for slot in self._table:
            if slot not in (HashTable.EMPTY, HashTable.UNUSED):
                yield slot.key


def test():
    import pytest
    h = HashTable()
    h.add('a', 0)
    h.add('b', 1)
    h.add('c', 2)
    assert len(h) == 3
    assert h.get('a') == 0
    assert h.get('b') == 1
    assert h.get('c') == 2
    assert h.get('asd') is None

    h.remove('a')
    assert h.get('a') is None
    assert sorted(list(h)) == ['b', 'c']

    n = 50
    for i in range(n):
        h.add(i, i)

    for i in range(n):
        assert h.get(i) == i



dict_adt

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class Array():
    def __init__(self, size=32, init=None):
        self._size = size
        self._items = [init] * size

    def __getitem__(self, index):
        return self._items[index]

    def __setitem__(self, index, value):
        self._items[index] = value

    def __len__(self):
        return self._size

    def clear(self, value=None):
        self._items = [value] * len(self._items)

    def __iter__(self):
        for item in self._items:
            yield item


class Slot():
    def __init__(self, key, value):
        self.key, self.value = key, value


class HashTable():
    UNUSED = None
    EMPTY = Slot(None, None)

    def __init__(self):
        self._table = Array(8, init=HashTable.UNUSED)
        self.length = 0

    @property
    def _load_factor(self):
        return self.length / float(len(self._table))

    def __len__(self):
        return self.length

    def _hash(self, key):
        return abs(hash(key)) % len(self._table)

    def _find_key(self, key):
        index = self._hash(key)
        _len = len(self._table)
        while self._table[index] is not HashTable.UNUSED:
            if self._table[index] is HashTable.EMPTY:
                index = (index * 5 + 1) % _len
                continue
            elif self._table[index].key == key:
                return index
            else:
                index = (index * 5 + 1) % _len
        return None

    def _slot_can_insert(self, index):
        return (self._table[index] is HashTable.EMPTY or self._table[index] is HashTable.UNUSED)

    def _find_slot_for_insert(self, key):
        index = self._hash(key)
        _len = len(self._table)
        while not self._slot_can_insert(index):
            index = (index * 5 + 1) % _len
        return index

    def __contains__(self, key):
        index = self._find_key(key)
        return index is not None

    def add(self, key, value):
        if key in self:
            index = self._find_key(key)
            self._table[index].value = value
            return False
        else:
            index = self._find_slot_for_insert(key)
            self._table[index] = Slot(key, value)
            self.length += 1
            if self._load_factor >= 0.8:
                self._rehash()
            return True

    def _rehash(self):
        old_table = self._table
        newsize = len(self._table) * 2
        self._table = Array(newsize, HashTable.UNUSED)
        self.length = 0

        for slot in old_table:
            if slot is not HashTable.UNUSED and slot is not HashTable.EMPTY:
                index = self._find_slot_for_insert(slot.key)
                self._table[index] = slot
                self.length += 1

    def get(self, key, default=None):
        index = self._find_key(key)
        if index is None:
            return default
        else:
            return self._table[index].value

    def remove(self, key):
        index = self._find_key(key)
        if index is None:
            raise KeyError()
        value = self._table[index].value
        self.length -= 1
        self._table[index] = HashTable.EMPTY
        return value

    def __iter__(self):
        for slot in self._table:
            if slot not in (HashTable.EMPTY, HashTable.UNUSED):
                yield slot.key


class DictADT(HashTable):

    def __setitem__(self, key, value):
        self.add(key, value)

    def __getitem__(self, key):
        if key not in self:
            raise KeyError()
        else:
            return self.get(key)

    def _iter_slot(self):
        for slot in self._table:
            if slot not in (HashTable.EMPTY, HashTable.UNUSED):
                yield slot

    def items(self):
        for slot in self._iter_slot():
            yield (slot.key, slot.value)

    def keys(self):
        for slot in self._iter_slot():
            yield slot.key

    def values(self):
        for slot in self._iter_slot():
            yield slot.value


def test():
    import random
    import pytest

    d = DictADT()

    d['a'] = 1
    assert d['a'] == 1
    d.remove('a')

    l = list(range(30))
    random.shuffle(l)
    for i in l:
        d.add(i, i)

    for i in range(30):
        assert d.get(i) == i

    assert sorted(list(d.keys())) == sorted(l)



set_adt

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class Array():
    def __init__(self, size=32, init=None):
        self._size = size
        self._items = [init] * size

    def __getitem__(self, index):
        return self._items[index]

    def __setitem__(self, index, value):
        self._items[index] = value

    def __len__(self):
        return self._size

    def clear(self, value=None):
        self._items = [value] * len(self._items)

    def __iter__(self):
        for item in self._items:
            yield item


class Slot():
    def __init__(self, key, value):
        self.key, self.value = key, value


class HashTable():
    UNUSED = None
    EMPTY = Slot(None, None)

    def __init__(self):
        self._table = Array(8, init=HashTable.UNUSED)
        self.length = 0

    @property
    def _load_factor(self):
        return self.length / float(len(self._table))

    def __len__(self):
        return self.length

    def _hash(self, key):
        return abs(hash(key)) % len(self._table)

    def _find_key(self, key):
        index = self._hash(key)
        _len = len(self._table)
        while self._table[index] is not HashTable.UNUSED:
            if self._table[index] is HashTable.EMPTY:
                index = (index * 5 + 1) % _len
                continue
            elif self._table[index].key == key:
                return index
            else:
                index = (index * 5 + 1) % _len
        return None

    def _slot_can_insert(self, index):
        return (self._table[index] is HashTable.EMPTY or self._table[index] is HashTable.UNUSED)

    def _find_slot_for_insert(self, key):
        index = self._hash(key)
        _len = len(self._table)
        while not self._slot_can_insert(index):
            index = (index * 5 + 1) % _len
        return index

    def __contains__(self, key):
        index = self._find_key(key)
        return index is not None

    def add(self, key, value):
        if key in self:
            index = self._find_key(key)
            self._table[index].value = value
            return False
        else:
            index = self._find_slot_for_insert(key)
            self._table[index] = Slot(key, value)
            self.length += 1
            if self._load_factor >= 0.8:
                self._rehash()
            return True

    def _rehash(self):
        old_table = self._table
        newsize = len(self._table) * 2
        self._table = Array(newsize, HashTable.UNUSED)
        self.length = 0

        for slot in old_table:
            if slot is not HashTable.UNUSED and slot is not HashTable.EMPTY:
                index = self._find_slot_for_insert(slot.key)
                self._table[index] = slot
                self.length += 1

    def get(self, key, default=None):
        index = self._find_key(key)
        if index is None:
            return default
        else:
            return self._table[index].value

    def remove(self, key):
        index = self._find_key(key)
        if index is None:
            raise KeyError()
        value = self._table[index].value
        self.length -= 1
        self._table[index] = HashTable.EMPTY
        return value

    def __iter__(self):
        for slot in self._table:
            if slot not in (HashTable.EMPTY, HashTable.UNUSED):
                yield slot.key


class SetADT(HashTable):

    def add(self, key):
        return super(SetADT, self).add(key, True)

    def __and__(self, other_set):
        new_set = SetADT()
        for element_a in self:
            if element_a in other_set:
                new_set.add(element_a)
        return new_set

    def __sub__(self, other_set):
        new_set = SetADT()
        for element_a in self:
            if element_a not in other_set:
                new_set.add(element_a)
        return new_set

    def __or__(self, other_set):
        new_set = SetADT()
        for element_a in self:
            new_set.add(element_a)
        for element_b in other_set:
            new_set.add(element_b)
        return new_set

    def __xor__(self, other_set):
        return (self | other_set) - (self & other_set)


def test():
    import pytest

    sa = SetADT()
    sa.add(1)
    sa.add(2)
    sa.add(3)
    assert 1 in sa

    sb = SetADT()
    sb.add(3)
    sb.add(4)
    sb.add(5)

    assert sorted(list(sa & sb)) == [3]
    assert sorted(list(sa - sb)) == [1, 2]
    assert sorted(list(sa | sb)) == [1, 2, 3, 4, 5]
    assert sorted(list(sa ^ sb)) == [1, 2, 4, 5]



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def binary_search(sorted_array, val):
    if not sorted_array:
        return -1

    beg = 0
    end = len(sorted_array) - 1

    while beg <= end:
        mid = beg + (end - beg) // 2
        if sorted_array[mid] == val:
            return mid
        elif sorted_array[mid] > val:
            end = mid - 1
        else:
            beg = mid + 1
    return -1


def binary_search_recursive(sorted_array, val, beg=0, end=None):
    if end is None:
        end = len(sorted_array) - 1

    if beg > end:
        return -1

    mid = beg + (end - beg) // 2

    if sorted_array[mid] == val:
        return mid

    if sorted_array[mid] > val:
        return binary_search_recursive(sorted_array, val, beg, mid - 1)
    else:
        return binary_search_recursive(sorted_array, val, mid + 1, end)


def test():
    import pytest

    asd = [1, 2, 3, 4, 5]
    assert binary_search(asd, 3) == 2
    assert binary_search_recursive(asd, 3) == 2

    dsa = [5, 4, 3, 2, 1]
    assert binary_search(asd, 3) == 2
    assert binary_search_recursive(asd, 3) == 2



bubble_sort

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import random


def bubble_sort(seq):
    n = len(seq)
    for i in range(n - 1):
        for j in range(n - 1 - i):
            if seq[j] > seq[j + 1]:
                seq[j], seq[j + 1] = seq[j + 1], seq[j]


def test_bubble_sort():
    seq = list(range(10))
    random.shuffle(seq)
    sorted_seq = sorted(seq)
    bubble_sort(seq)
    assert seq == sorted_seq


def select_sort(seq):
    n = len(seq)
    for i in range(n - 1):
        min_idx = i
        for j in range(i + 1, n):
            if seq[j] < seq[min_idx]:
                min_idx = j
        if min_idx != i:
            seq[i], seq[min_idx] = seq[min_idx], seq[i]


def test_select_sort():
    seq = list(range(10))
    random.shuffle(seq)
    sorted_seq = sorted(seq)
    select_sort(seq)
    assert seq == sorted_seq


def insertion_sort(seq):
    n = len(seq)
    for i in range(1, n):
        value = seq[i]
        pos = i
        while pos > 0 and value < seq[pos - 1]:
            seq[pos] = seq[pos - 1]
            pos -= 1
        seq[pos] = value


def test_insertion_sort():
    seq = list(range(10))
    random.shuffle(seq)
    sorted_seq = sorted(seq)
    insertion_sort(seq)
    assert seq == sorted_seq



merge_sort

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def merge_sort(seq):
    if len(seq) <= 1:
        return seq
    else:
        mid = int(len(seq) / 2)
        left_half = merge_sort(seq[:mid])
        right_half = merge_sort(seq[mid:])

        new_seq = merge_sorted_list(left_half, right_half)
        return new_seq


def merge_sorted_list(sorted_a, sorted_b):
    length_a, length_b = len(sorted_a), len(sorted_b)
    a = b = 0
    new_sorted_seq = list()

    while a < length_a and b < length_b:
        if sorted_a[a] < sorted_b[b]:
            new_sorted_seq.append(sorted_a[a])
            a += 1
        else:
            new_sorted_seq.append(sorted_b[b])
            b += 1

    while a < length_a:
        new_sorted_seq.append(sorted_a[a])
        a += 1

    while b < length_b:
        new_sorted_seq.append(sorted_b[b])
        b += 1

    return new_sorted_seq


def test():
    import random

    seq = list(range(10))
    random.shuffle(seq)
    assert merge_sort(seq) == sorted(seq)



quick_sort

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def quicksort(array):
    if len(array) < 2:
        return array
    else:
        pivot_index = 0
        pivot = array[pivot_index]
        less_part = [i for i in array[pivot_index + 1:] if i <= pivot]
        great_port = [i for i in array[pivot_index + 1:] if i > pivot]
        return quicksort(less_part) + [pivot] + quicksort(great_port)


def test():
    import random

    seq = list(range(10))
    random.shuffle(seq)
    assert quicksort(seq) == sorted(seq)


def partition(array, beg, end):
    pivot_index = beg
    pivot = array[pivot_index]
    left = pivot_index + 1
    right = end - 1

    while True:
        while left <= right and array[left] < pivot:
            left += 1

        while right >= left and array[right] >= pivot:
            right -= 1

        if left > right:
            break
        else:
            array[left], array[right] = array[right], array[left]

    array[pivot_index], array[right] = array[right], array[pivot_index]
    return right


def test_partition():
    l = [4, 1, 2, 8]
    assert partition(l, 0, len(l)) == 2
    l = [1, 2, 3, 4]
    assert partition(l, 0, len(l)) == 0
    l = [4, 3, 2, 1]
    assert partition(l, 0, len(l)) == 3


def quicksort_inplace(array, beg, end):
    if beg < end:
        pivot = partition(array, beg, end)
        quicksort_inplace(array, beg, pivot)
        quicksort_inplace(array, pivot + 1, end)
    return array


def test_quicksort_inplace():
    import random

    seq = list(range(10))
    random.shuffle(seq)
    assert quicksort_inplace(seq, 0, len(seq)) == sorted(seq)