linked_list.py - master - erddrsf/Pyhse

linked_list.py
154 строки5 KB
erddrsf
Примеры моего кода
01 май 2026, 23:35
01 май 2026, 23:35b05b859
class Linked_Node():
    def __init__(self, value=0, next=None):
        self.value = value
        self.next = next

class Linked_list():
    def __init__(self):
        self.head = None
        self.tail = None

    def len_list(self):
        count = 0
        node = self.head
        while node is not None:
            count += 1
            node = node.next
        return count

    def find_middle(self):
        if self.head is None:
            print("Список пустой")
            return None
        slow = self.head
        fast = self.head
        while fast is not None and fast.next is not None:
            slow = slow.next
            fast = fast.next.next
        return slow

    def add_first(self, node):
        if not isinstance(node, Linked_Node):
            print("Ошибка: добавляемый элемент не является Linked_Node")
            return
        if self.head is None and self.tail is None:
            self.head = node
            self.tail = node
        else:
            node.next = self.head
            self.head = node

    def add_at(self, node_insert, idx):
        if not isinstance(node_insert, Linked_Node):
            print("Ошибка: добавляемый элемент не является Linked_Node")
            return
        length = self.len_list()
        if idx < 0 or idx > length:
            print("Ошибка: некорректный индекс")
            return
        if idx == 0:
            self.add_first(node_insert)
            return
        node = self.head
        for i in range(idx - 1):
            node = node.next
        node_insert.next = node.next
        node.next = node_insert
        if node_insert.next is None:
            self.tail = node_insert

    def add_last(self, node):
        if not isinstance(node, Linked_Node):
            print("Ошибка: добавляемый элемент не является Linked_Node")
            return
        if self.head is None and self.tail is None:
            self.head = node
            self.tail = node
        else:
            self.tail.next = node
            self.tail = node

    def delete_first(self):
        if self.head is None:
            print("Ошибка: список уже пуст")
            return
        if self.head.next is None:
            self.head = None
            self.tail = None
        else:
            self.head = self.head.next

    def delete_at(self, idx):
        length = self.len_list()
        if self.head is None:
            print("Ошибка: список пуст")
            return
        if idx < 0 or idx >= length:
            print("Ошибка: некорректный индекс")
            return
        if idx == 0:
            self.delete_first()
            return
        node = self.head
        for i in range(idx - 1):
            node = node.next
        if node.next is None:
            print("Ошибка: индекс вне диапазона")
            return
        node.next = node.next.next
        if node.next is None:
            self.tail = node

    def delete_last(self):
        if self.head is None:
            print("Ошибка: список пуст")
            return
        if self.head.next is None:
            self.head = None
            self.tail = None
            return
        node = self.head
        while node.next != self.tail:
            node = node.next
        node.next = None
        self.tail = node

    def print_all_list(self):
        if self.head is None:
            print("пустой список")
            return
        node = self.head
        while node is not None:
            print(node.value)
            node = node.next

    def detect_cycle_and_length(self):
        slow = self.head
        fast = self.head
        while fast is not None and fast.next is not None:
            slow = slow.next
            fast = fast.next.next
            if slow == fast:
                cycle_length = 1
                current = slow
                while current.next != slow:
                    current = current.next
                    cycle_length += 1
                return cycle_length
        return 0

    def find_kth_from_end(self, k):
        if k < 1:
            print("Ошибка: k должно быть положительным числом")
            return None
        first = self.head
        second = self.head
        for _ in range(k):
            if first is None:
                print("Ошибка: k больше длины списка")
                return None
            first = first.next
        while first is not None:
            first = first.next
            second = second.next
        return second