Chain structure-head insertion method-reverse order
- To construct a singly linked list (head insertion method), the
head insertion method is to insert each new node into the head of the linked list, so it is the reverse order of your input. These two functions are head insertion and tail insertion. You can change the call in the main function to tail insertion.
#include <stdio.h>
#include <windows.h>
#include <stdlib.h>
typedef int ElemType;
typedef struct node{
ElemType data;
struct node *next;
} Node, *LinkList;
/*链表的初始化*/
LinkList init(){
LinkList p;
p=(LinkList)malloc(sizeof(Node));
p->next=NULL;
return p;
}
/*求表长*/
int len(LinkList H){
int len=0;
LinkList p;
for(p=H->next; p; p=p->next) len++;
return len;
}
/*头部插入法*/
void f_insert(LinkList H,ElemType s){
LinkList p,q;
p=(LinkList)malloc(sizeof(Node));
p->next=NULL;
p->data=s;
p->next=H->next;
H->next=p;
}
/*尾部插入法*/
LinkList r_insert(LinkList H,ElemType s){
LinkList p,q;
for(q=H; q->next; q=q->next);
p=(LinkList)malloc(sizeof(Node));
p->next=NULL;
p->data=s;
q->next=p;
return p;
}
/*删除p指向的结点*/
void dele(LinkList H,LinkList p){
LinkList q;
for(q=H; q->next!=p; q=q->next);
q->next=p->next;
free(p);
}
/*按值查找*/
LinkList search_val(LinkList H,ElemType s){
LinkList p;
for(p=H->next; p; p=p->next)
if(p->data==s)
return p;
return NULL;
}
/*按序号查找，序号从1开始*/
LinkList search_no(LinkList H,int pos){
LinkList p;
int i=1;
if(pos<=0 || pos>len(H))
{
printf("输入的序号不合法！\n");
return NULL;
}
for(p=H->next; i!=pos; p=p->next)i++;
return p;
}
/*输出所有链表值*/
void print_all(LinkList H)
{
LinkList p;
for(p=H->next; p; p=p->next)
printf("%d ",p->data);
printf("\n");
}
/*在单链表H的第pos个结点前插入值为e的结点,pos从1开始*/
int insert(LinkList H,int pos,ElemType e)
{
LinkList p,q;
if(pos>len(H) || pos<1)
{
printf("输入的位置不合法\n");
return 0;
}
else if(pos==1) f_insert(H,e);
else
{
p=search_no(H,pos-1);
q=(LinkList)malloc(sizeof(Node));
q->data=e;
q->next=p->next;
p->next=q;
}
return 1;
}
/*递增有序链表La,Lb合并为Lc*/
void merge(LinkList La,LinkList Lb,LinkList *Lc)
{
LinkList pa,pb,pc;
pa=La->next;
pb=Lb->next;
(*Lc)=pc=La;/*pc总是指向生成的单链表的最后一个结点*/
while(pa && pb)
{
if(pa->data <= pb->data)
{
pc->next = pa; /*将pa连接到pc之后*/
pc = pa;
pa = pa->next;
}
else
{
pc->next = pb;
pc = pb;
pb = pb->next;
}
}
/*La单链表还有结点时,剩余结点放在pc后，否则Lb剩余结点放在pc后*/
pc->next = pa? pa:pb;
}
void destroy(LinkList H)
{
LinkList p=H,q=p->next;
while(q)
{
free(p);
p=q;
q=p->next;
}
free(p);
}
int main()
{
LinkList H,Ha,Hb,Hc,p;
int n,menu,i;
ElemType e;
H=init();/*初始化带头结点的单链表,头指针为H,*/
Ha=init();/*初始化带头结点的单链表,头指针为Hb,*/
Hb=init();/*初始化带头结点的单链表,头指针为Ha,*/
do/*菜单*/
{
printf("\n\n*******************单链表操作*******************\n");
printf("1.构建单链表(头部插入法)\n");
printf("2.输出单链表各值\n");
printf("3.输出单链表表长\n");
printf("4.向单链表插入结点\n");
printf("5.删除单链表某结点\n");
printf("6.按序号查找单链表结点\n");
printf("7.归并有序单链表\n");
printf("8.退出程序\n");
printf("输入菜单号码:\n");
scanf("%d",&menu);
switch(menu)
{
case 1:
destroy(H);
H=init();
printf("输入要插入结点个数：\n");
scanf("%d",&n);
printf("输入要插入的%d个结点值,各值用空格分隔：\n",n);
for(i=0; i<n; i++)
{
scanf("%d",&e);
f_insert(H,e);/*在链表H头部插入值e*/
}
printf("单链表创建成功!\n");
Sleep(500);
system("cls");
break;
case 2:
printf("链表各元素为:\n");
print_all(H);
system("pause");
system("cls");
break;
case 3:
printf("单链表表长为%d\n",len(H));
system("pause");
system("cls");
break;
case 4:
printf("输入插入的位置:\n");
scanf("%d",&n);
printf("输入插入的元素值:\n");
scanf("%d",&e);
if(insert(H,n,e))
{
printf("插入元素%d后各值为:\n",e);
print_all(H);
}
system("pause");
break;
case 5:
printf("输入要删除的元素值\n");
scanf("%d",&e);
if((p=search_val(H,e))!=NULL)
{
dele(H,p);
printf("删除元素%d后各值为:\n",e);
print_all(H);
}
else printf("元素%d不存在!\n",e);
system("pause");
break;
case 6:
printf("输入要查找的元素序号:\n");
scanf("%d",&n);
if((p=search_no(H,n))!=NULL)
printf("链表第%d个元素为:%d\n",n,p->data);
system("pause");
break;
case 7:
destroy(Ha);
destroy(Hb);
Ha=init();
Hb=init();
printf("输入有序单链表Ha结点个数:\n");
scanf("%d",&n);
printf("输入有序单链表Ha的%d个结点值,各值用空格分隔:\n",n);
for(i=0; i<n; i++){
scanf("%d",&e);
r_insert(Ha,e);/*在链表Ha尾部插入值e*/
}
printf("输入有序单链表Hb结点个数:\n");
scanf("%d",&n);
printf("输入有序单链表Hb的%d个结点值,各值用空格分隔:\n",n);
for(i=0; i<n; i++){
scanf("%d",&e);
r_insert(Hb,e);/*在链表Hb尾部插入值e*/
}
merge(Ha,Hb,&Hc);
printf("合并后的有序单链表各值为:\n");
print_all(Hc);
system("pause");
break;
case 8:
destroy(H);/*删除链表H*/
destroy(Ha);/*删除链表Ha*/
destroy(Hb);/*删除链表Hb*/
return 0;
default:
printf("输入的菜单号有误!\n");
system("pause");
break;
}
}
while(1);
return 0;}