线性表采用链式存储结构：编写程序实现以下功能

1、建立单链表

2、打印单链表

3、在单链表的第i个结点前插入一个新元素，并打印新的单链表

4、删除单链表的第i个结点，并打印新的单链表

-Linear form a chain storage structure: write a program to achieve the following functions



1, the establishment of a single linked list



2, print list



In3, a single list of the I node before inserting a new element, and print a new single linked list



In 4, the deletion of a single list of I nodes, and print a new single linked list