[edu] double linked list (with node)

[폰트사이즈18 고딕 진하게]

폰트 사이즈 12 고딕

폰트 사이즈 12 고딕

폰트 사이즈 12 고딕

폰트 사이즈 12 고딕

폰트 사이즈 12 고딕

폰트 사이즈 12 고딕

리팩토링 후

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


class DList:
    def __init__(self):
        self.head = Node()
        self.tail = Node(prev=self.head)
        self.head.next = self.tail
        self.size = 0

    def is_empty(self):
        return not bool(self.size)

    def insert(self, data, front, rear):
        new_node = Node(data, front, rear)
        front.next, rear.prev = new_node, new_node
        self.size += 1

    def insert_front(self, data): self.insert(data, self.head, self.head.next)

    def insert_rear(self, data): self.insert(data, self.tail.prev, self.tail)

    def get_final(self, index):
        assert 0 <= index < self.size, "double linked list out of range"
        final_node, cur_index = self.head.next, 0
        while cur_index < index:
            final_node, cur_index = final_node.next, cur_index + 1
        return final_node

    def insert_mid(self, data, index):
        final_node = self.get_final(index)
        self.insert(data, final_node, final_node.next)

    def delete_index(self, index):
        target = self.get_final(index)
        target.prev.next, target.next.prev = target.next, target.prev
        self.size -= 1

    def __str__(self):
        cur = self.head.next
        sb = ""
        while cur.next:
            sb += str(cur.data) + " "
            cur = cur.next
        return sb


dlist = DList()
dlist.insert_front(1)
dlist.insert_front(2)
dlist.insert_front(3)
print(dlist)
dlist.delete_index(2)
# print(dlist)
# dlist.insert_mid(99, 0)
# dlist.insert_rear(-1)
print(dlist)

리팩토링 전

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


class DList:
    def __init__(self):
        self.head = Node()
        self.tail = Node(prev=self.head)
        self.head.next = self.tail
        self.size = 0

    def is_empty(self):
        return not bool(self.size)

    def insert_front(self, data):
        new_node = Node(data, self.head, self.head.next)
        first_node = self.head.next
        first_node.prev = new_node
        self.head.next = new_node
        self.size += 1

    def insert_rear(self, data):
        new_node = Node(data, self.tail.prev, self.tail)
        final_node = self.tail.prev
        final_node.next = new_node
        self.tail.prev = new_node
        self.size += 1

    def get_final(self, index):
        assert 0 <= index < self.size, "double linked list out of range"
        final_node, cur_index = self.head.next, 0
        while cur_index < index:
            final_node = final_node.next
            cur_index += 1
        return final_node

    def insert_mid(self, data, index):
        final_node = self.get_final(index)
        new_node = Node(data, final_node, final_node.next)
        final_node.next = new_node
        final_node.next.prev = new_node
        self.size += 1

    def delete_index(self, index):
        final_node = self.get_final(index)
        front = final_node.prev
        rear = final_node.next
        front.next = rear
        rear.prev = front
        self.size -= 1

    def __str__(self):
        cur = self.head.next
        sb = ""
        while cur.next:
            sb += str(cur.data) + " "
            cur = cur.next
        return sb


dlist = DList()
dlist.insert_rear(1)
dlist.insert_rear(2)
dlist.insert_rear(3)
print(dlist)
# dlist.delete_index(0)
# print(dlist)
# dlist.insert_mid(-1, 3)
dlist.insert_rear(-1)
print(dlist)