feat: 单向链表添加

Author: juwenzhang

Single_linked_list.py

@@ -0,0 +1,243 @@
+# 先实现定义自己的一个一个的节点
+class Node(object):
+    def __init__(self, data) -> None:
+        # 一个节点的数据域
+        self.data = data
+        # 一个节点的指针域,其存储的是下一个节点的内存地址
+        self.next = None
+
+
+class SingleLinkedList:
+    # 在进行实例化的时候我们该有一个初始节点的，通过这个初始节点来实现寻找我们的链表，这个就是头节点了
+    def __init__(self) -> None:
+        self.__head = None
+
+
+    # 获取链表长度
+    def __get_length_link(self) -> int:
+        """
+        获取链表长度
+        :return:
+        """
+        p = self.__head
+        count = 1
+        while p.next is not None:
+            p = p.next  # 更新指向
+            count += 1
+        return count
+
+
+    # 实现一个函数来保存数据
+    def __save_data_in_list(self) -> list:
+        """
+        将链表元素组成一个列表返回
+        :return:
+        """
+        data_list = []
+        current = self.__head
+        while current is not None:
+            data_list.append(current.data)
+            current = current.next
+        return data_list
+
+
+    # 添加单个节点操作
+    def append_one_node(self, data) -> None:
+        """
+        一次性添加一个元素
+        :param data: append element`s value
+        :return: None
+        """
+        # 将元素转化为节点
+        node = Node(data)
+        # 判断头节点是否为空
+        if self.__head is None:
+            self.__head = node
+
+        # 如果不为空，那就将节点挂载在有值的节点上面
+        else:
+            current = self.__head
+            # 如果节点为空，那就直接实现节点的偏移
+            while current.next:
+                current = current.next
+            current.next = node
+
+
+    # 添加多个节点
+    def append_many_node(self, list_data: list) -> None:
+        """
+        一次性插入多个元素
+        :param list_data:
+        :return:
+        """
+        # 直接遍历列表，实现循环添加单个节点
+        for data in list_data:
+            self.append_one_node(data)
+
+
+    # 通过下标添加节点
+    def append_node_by_index(self, index: int, data) -> None:
+        """
+        通过下标插入元素
+        :param index:
+        :param data:
+        :return:
+        """
+        if index < 1:
+            raise IndexError("Index must be greater than 0 \n")
+        if index > self.__get_length_link():
+            raise IndexError("index out of range!!!\n")
+
+        current_node = self.__head
+        node = Node(data)
+
+        if index == 1:
+            node.next = self.__head
+            self.__head = node
+        else:
+            # 中间节点的插入
+            current_index = 1  # 记录节点的下标
+            # 实现偏移
+            while current_node and current_index < index - 1:
+                current_node = current_node.next
+                current_index += 1
+            # 插入新节点
+            node.next = current_node.next
+            current_node.next = node
+
+
+    # 遍历显示所有的元素
+    def show_link_data(self) -> None:
+        """
+        显示链表啊所有的元素
+        :return:
+        """
+        if self.__head is None:
+            print("链表为空")
+        else:
+            # 从头结点依次遍历整个链表元素
+            current = self.__head
+            while current is not None:
+                print(current.data, end=" ")
+                current = current.next
+            print("\n")
+
+
+    # 通过下标实现查找元素: 这里的使用列表实现的话，时间复杂度有是常数级别的查找元素
+    def show_data_by_index(self, index: int) -> None:
+        """
+        通过下标显示元素
+        :param index:
+        :return:
+        """
+        # 或者说和随机插入元素的思路实现一样的，但是这里的话我是前面提前将数据添加入了一个列表中的
+        if index > self.__get_length_link():
+            raise IndexError("index out of range!!!")
+        data_link_list = self.__save_data_in_list()
+        print(f"第{index}个元素为: {data_link_list[index - 1]}\n")
+
+
+    # 删除整个链表
+    def clear_link(self) -> None:
+        """
+        清空链表
+        :return:
+        """
+        self.__head = None
+
+
+    # 根据下标删除元素
+    def delete_link_by_index(self, index: int) -> None:
+        """
+        根据下标删除元素
+        :param index:
+        :return:
+        """
+        if index < 1:
+            raise IndexError("Index must be greater than 0 \n")
+        if index > self.__get_length_link():
+            raise IndexError("index out of range!!!\n")
+
+        if index == 1:
+            self.__head = self.__head.next
+            return
+
+        current = self.__head
+        current_index = 1
+        while current and current_index < index - 1:
+            current = current.next
+            current_index += 1
+        new_current = current.next
+        current.next = current.next.next
+        new_current.next = None
+
+
+    # 根据值来进行删除元素
+    def delete_link_by_value(self, value) -> None:
+        """
+        根据值来删除元素
+        :param value:
+        :return:
+        """
+        # 头节点直接改变头节点指向即可
+        if self.__head.data == value:
+            self.__head = self.__head.next
+            return
+
+        current = self.__head
+        while current.next:
+            if current.next.data == value:
+                current.next = current.next.next
+                return
+            current = current.next
+        if current.next is None:
+            raise ValueError("value is not find")
+
+
+    # 根据下标修改元素
+    def set_link_by_index(self, index: int, data) -> None:
+        """
+        根据下标修改元素
+        :param index:
+        :param data:
+        :return:
+        """
+        if index < 1:
+            raise IndexError("Index must be greater than 0 \n")
+        if index > self.__get_length_link():
+            raise IndexError("index out of range!!!\n")
+
+        if index == 1:
+            self.__head.data = data
+            return
+
+        current = self.__head
+        current_index = 1
+        # 偏移指针
+        while current and current_index < index:
+            current_index += 1
+            current = current.next
+        current.data = data
+
+
+    # 根据值来进行修改链表的值
+    def set_link_by_value(self, value, data) -> None:
+        """
+        根据值来进行修改元素
+        :param value: 指定需要用来查找的指标
+        :param data: 需要进行替换的元素
+        :return:
+        """
+        current = self.__head
+        if current.data == value:
+            current.data = data
+            return
+
+        while current.next:
+            if current.next.data == value:
+                current.next.data = data
+                return
+            current = current.next
+
+        if current.next is None:
+            raise ValueError("value is not find!!!")