Data_Struct(LinkList)

　　最近在学数据结构，学到链表这节作业有链表，毕竟菜鸟代码基本照看书上算法写的，再加上自己的小修改，这里先记录下来，万一哪天想看了，来看看。

　　里面有用到二级指针，还是不太理解，还有就是注释不多，后续有了更好的理解，再来添加

 #define TRUE                    1
 #define FALSE                    0
 #define OK                    1
 #define ERROR                    0
 #define OVERFLOW                    -2
 #define INFEASIBLE                    -1
 #define Status                    int
 #define ElemType                int

 typedef struct LNode
 {
     ElemType data;
     struct LNode *next;
 }LNode;

 typedef LNode LinkList;
 Status ListInsert_L(LinkList L, int i, ElemType e);//插入函数
 Status ListDelete_L(LinkList L, int i, ElemType *e);//删除某个元素
 void CreateList_L(LinkList L, int n);//创建一个带头结点的空链表
 void MergeList_L(LinkList *La, LinkList *Lb, LinkList **Lc);   //合并两个有序链表         

LinkList.h

 #include <stdio.h>
 #include <stdlib.h>
 #include <malloc.h>
 #include "LinkList.h"

 //新建带头结点的空链表
 void CreateList_L(LinkList **L, int n)
 {
     int i; LinkList *p = NULL;
     (*L) = (LinkList*) malloc (sizeof (LNode));
     (*L) ->next = NULL;
     printf("请输入链表元素 :\n");
     for(i = n; i > ; --i)
     {
         p = (LinkList*) malloc (sizeof (LNode));//生成新结点
         scanf("%d", &p -> data);//输入元素值
         p -> next = (*L) -> next;
         (*L) -> next = p;//插入到表头
     }
 }

 //插入元素
 Status ListInsert_L(LinkList *L, int i, ElemType e)
 {
     LinkList *p = L;
     LinkList *s = NULL;
     int j = ;
     while (p->next && j < i - )
     {
         p = p -> next;
         ++ j;
     }
     if(!p || j != i - )
     return ERROR;
     s = (LinkList*) malloc (sizeof(LNode));
     s -> data = e;
     s -> next = p ->next;
     p -> next = s;
     return OK;
 }

 //删除元素
 Status ListDelete_L(LinkList *L, int i, ElemType *e)
 {
     LinkList *p = L;
     LinkList *q;
     int j = ;
     while(p -> next && j < i - )
     {
         p = p -> next;
         ++ j;
     }
     if(!(p -> next) || j > i - )
         return ERROR;
     q = p -> next;
     p -> next = q -> next;
     *e= q -> data;
     free(q);
     return OK;
 }

 void MergeList_L(LinkList *La, LinkList *Lb, LinkList **Lc)
 {
     LinkList *pa = La -> next;
     LinkList *pb = Lb -> next;
     LinkList *pc = NULL;
     (*Lc) = pc =  La;
     while(pa && pb)
     {
         if(pa -> data <= pb -> data)
         {
             pc -> next = pa;
             pc = pa;
             pa = pa ->next;
         }
         else
         {
             pc -> next = pb;
             pc = pb;
             pb = pb -> next;
         }
     }
         pc -> next = pa ? pa : pb;//插入剩余段
         free(Lb);//释放Lb头结点
         Lb = NULL;

 }

 void Free(LinkList *L)
 {
     if(L && L -> next)
          Free( L -> next);
     free(L);
     return;
 }

 int main()
 {
         int selectn,length0,length1,location,e,counti;
         LNode *L1 = NULL,*L2 = NULL, *L3 = NULL, *la = NULL, *lc = NULL;
         printf("请输入新链表长度 ：\n");
         scanf("%d", &length0);
         CreateList_L(&L1, length0);
         printf("请选择 : \n");
         printf("1 : 插入元素\n");
         printf("2 : 删除元素\n");
         printf("3 : 合并链表\n");
         scanf("%d", &selectn);
         switch (selectn)
         {
         case  :
             printf("请输入插入位置 ：\n");
             scanf("%d", &location);
             printf("请输入要插入元素 ：\n");
             scanf("%d", &e);
             if(ListInsert_L(L1, location, e) == OK )
                 {   //逆序输出
                     counti = ;
                     la = L1;
                     printf("新链表的顺序为 ：\n");
                     while(la -> next)
                     {
                         la = la->next;
                         if(counti++ % )
                             printf("%-5d",la -> data);
                         else
                             printf("%-5d\n",la -> data);
                     }
                 }
             else
                 printf("插入异常\n");
                 printf("\n");
             break;
         case  :
             printf("请输入要删除的位置 :\n");
             scanf("%d",&location);
             if(ListDelete_L(L1, location, &e) == OK)
             {
                 printf("删除成功\n被删除元素为 : %-5d\n", e);
             }
             else
                 printf("删除异常\n");
             break;
         case  :
             printf("请输入链表2 :\n");
             printf("请输入链表长度 :\n");
             scanf("%d", &length1);
             CreateList_L(&L2, length1);
             MergeList_L(L1, L2, &L3);
             L2 = NULL;
             lc = L3 -> next;
             printf("新链表顺序为 :\n");
             counti = ;
             while(lc)
             {    if(counti++ % )
                     printf("%-5d", lc -> data);
                 else
                     printf("%-5d", lc -> data);
                 lc = lc -> next;
             }
             printf("\n");
             break;
         default :
             printf("ERROR\n");
             break;
         }
         Free(L1);
         L1    = NULL;
         L3    = NULL;
         system("pause");
         return ;
 }