TEST

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


# 头插法
class SingalNode:
    def __init__(self):
        self.head = None

    def add(self, data):
        node = Node(data)
        node.next_ = self.head
        self.head = node
        return

    def traveList(self):
        current_node = self.head
        while current_node:
            print(current_node.data)
            current_node = current_node.next_

    def is_empty(self):
        if self.head == None:
            return False
        else:
            return True

    def get_length(self):
        num = 0
        current_node = self.head
        while current_node:
            num += 1
            current_node = current_node.next_
        return num

    def insert_node(self, data, index):
        '''
        链表插入数据函数
        :param data:
        :param index:
        :return:
        '''
        link_len=self.get_length()

        if isinstance(index, int):
            if index < 0:
                self.insert_node(data,0)
            if index >link_len:
                self.insert_node(data,link_len)
            else:
                node = Node(data)
                current_node = self.head
                cnt = 1
                while current_node:
                    if index==0:
                        node.next_ = current_node
                        self.head=node
                        return
                    elif index==cnt:
                        node.next_=current_node.next_
                        current_node.next_=node
                        return
                    else:
                        # 移动游标
                        current_node = current_node.next_
                        # 计数器加1
                        cnt += 1
        else:
            print("pos位置无效, 请确认")
            exit()



if __name__ == '__main__':
    test = SingalNode()
    # print(test.head)
    #print(test.is_empty())
    data_list = [1, 3, 5]
    for i in data_list:
        test.add(i)
    #print(test.head)
    test.traveList()
    #print(test.is_empty())
    #print(test.get_length())
    print ('test')
    test.insert_node(9,2)
    test.traveList()