头插法建立单链表

#define NULL 0
#include<stdio.h>typedef struct LNode
{int data;struct LNode *next;
}LNode,*LinkList;//单链表尾插法
LinkList List_TailInsert(LinkList &L){int x;L = (LinkList)malloc(sizeof(LNode));        //初始化空表LNode *r = L;            //r为表尾指针scanf("&d",&x);while (x!=9999)             //输入9999表示结束{LNode *s = (LNode*)malloc(sizeof(LNode));s->data = x;r->next = s;r = s;scanf("%d",&x);}r->next = NULL;         //r尾结点指针置空return L;
}

尾插法建立单链表

//单链表头插法
LinkList List_TailInsert(LinkList &L){int x;L = (LinkList)malloc(sizeof(LNode));        //初始化空表L->next = NULL;             //必须置空！不然一直会指向未知区域！！！scanf("&d",&x);while (x!=9999)             //输入9999表示结束{LNode *s = (LNode*)malloc(sizeof(LNode));s->data = x;s->next = L->next;L->next = s;            //插入成功scanf("%d",&x);}return L;
}