实现功能：
1. 定义结构体
cpp
typedef int data_t;
typedef struct note
{
data_t data;
struct note *next;
}listnote, *linklist;data_t data;：定义了一个名为data的字段，其类型为data_t；
struct note *next;：定义了一个名为next的指针字段，该指针指向与当前结构体相同
类型的下一个结构体
listnote是struct note的别名
linklist是一个指向struct note的指针的别名
2. 创建一个空链表
cpp
linklist list_create(){
linklist H;
//1. 申请内存
H = (linklist)malloc(sizeof(listnote));
if(H ==NULL){
printf("malloc failed\n");
}
//2. 赋初值
H->data = 0;
H->next = NULL;
//3. 返回值
return H;
}3. 尾部插入和遍历
尾部插入分为三步：1. 建立一个新节点
①malloc
②赋初值
-
找尾节点
-
实现尾部插入
cpp
int list_tail_insert(linklist H,data_t value){
if (H == NULL)
{
printf("H is NULL\n");
return -1;
}
//1.new a note
linklist p;
linklist q;
if ((p=(linklist)malloc(sizeof(listnote)))== NULL)
{
printf("malloc is failed\n");
return -1;
}
p->data = value;
p->next = NULL;
//2. find tail list
q = H;
while (q->next != NULL)
{
q = q->next;
}
//3. fail insert
q->next = p;
return 0;
}
int list_show(linklist H){
if (H == NULL)
{
printf("H is NULL\n");
return -1;
}
linklist p;
p = H;
while (p->next != NULL)
{
printf("%d ",p->next->data);
p = p->next;
}
puts("");
}
cpp
//main函数
#include <stdio.h>
#include "linklist.h"
int main(int argc, char const *argv[])
{
linklist H;
int value;
H = list_create();
if(H == NULL){
return -1;
}
printf("input:");
while (1)
{
scanf("%d",&value);
if(value == -1){
break;
}
list_tail_insert(H,value);
printf("input:");
}
return 0;
}遍历：
cpp
int list_show(linklist H){
if (H == NULL)
{
printf("H is NULL\n");
return -1;
}
linklist p;
p = H;
while (p->next != NULL)
{
printf("%d ",p->next->data);
p = p->next;
}
puts("");
}4. 通过序号查找值
cpp
linklist list_get(linklist H,int pos){
int i =-1;
linklist p;
p = H;
if(pos == -1){
return H;
}
while (i < pos)
{
p = p->next;
if (p == NULL)
{
printf("pos is invalid\n");
return NULL;
}
i++;
}
return p;
}
cpp
//main函数
p =list_get(H, 2);
if (p != NULL)
{
printf("value = %d\n",p->data);
}5. 在某一位置插入元素
cpp
int list_insert(linklist H,data_t value,int pos){
linklist p;
linklist q;
if (H == NULL)
{
printf("H is NULL\n");
return -1;
}
// 1. 定位节点 p （pos-1）
p =list_get(H,pos-1);
if (p == NULL)
{
printf("p is NULL\n");
return -1;
}
// 2. 新节点q申请内存，赋初值
if ((q = (linklist)malloc(sizeof(listnote)))== NULL)
{
printf("malloc failed\n");
return -1;
}
q->next = NULL;
q->data = value;
//3.完成插入操作
q->next = p->next;
p->next = q;
return 0;
}6. 链表删除某个元素
-
检查链表的入口参数
-
找前驱
-
更新链表
-
释放删除的内存
cpp
int list_del(linklist H,int pos){
linklist p;
linklist q;
//1.
if(H == NULL){
printf("H is NULL\n");
return -1;
}
//2.
p = list_get(H,pos-1);
if(p == NULL){
return -1;
}
if(p->next == NULL){
printf("delete pos invalid\n");
return -1;
}
//3.
q = p->next;
p->next = q->next;
//4.
printf("free = %d\n",q->data);
free(q);
q = NULL;
return 0;
}7. 释放链表内存
cpp
linklist list_free(linklist H){
linklist p;
if (H == NULL)
{
return NULL;
}
p = H;
printf("free:");
while (H != NULL)
{
p = H;
printf("%d ",p->data);
H = H->next;
free(p);
}
puts("");
return NULL;
}8. 链表反转
cpp
int list_inver(linklist H){
linklist p;
linklist q;
if (H == NULL)
{
printf("H is NULL\n");
return -1;
}
if (H->next == NULL ||H->next->next == NULL)
{
return 0;
}
p = H->next->next;
H->next->next = NULL;
while (p != NULL)
{
q = p;
p =p->next;
q->next = H->next;
H->next = q;
}
return 0;
}9. 求相邻结点最大值
cpp
//linklist.c 部分
linklist list_adjmax(linklist H,data_t *value){
linklist p , q, r;
data_t sum = 0;
if (H == NULL)
{
printf("H is NULL\n");
return NULL;
}
if(H->next == NULL ||H->next->next == NULL || H->next->next->next == NULL){
return H;
}
q = H->next;
p = q->next;
r = q;
sum = p->data + q->data;
while (p->next != NULL)
{
p = p->next;
q = q->next;
if (sum < p->data + q->data)
{
sum =p->data + q->data;
r = q;
}
}
*value = sum;
return r;
}
cpp
//main
linklist r;
int sum;
r = list_adjmax(H,&sum);
if (r != NULL && r != H)
{
printf("data=%d,sum=%d\n",r->data,sum);
}10. 合并两个有序链表
cpp
//linklist.c
int list_merge(linklist H,linklist R){
linklist p,q,r;
if (H == NULL)
{
printf("H is NULL\n");
return -1;
}
if (R == NULL)
{
printf("R is NULL\n");
return -1;
}
p = H->next;
q = R->next;
r = H;
H->next = NULL;
R->next = NULL;
while (p && q)
{
if (p->data <= q->data)
{
r->next = p;
p = p->next;
r = r->next;
r->next = NULL;
}else{
r->next = q;
q = q->next;
r = r->next;
r->next = NULL;
}
if (q == NULL)
{
r->next = p;
}else{
r->next = q;
}
}
return 0;
}
cpp
//main.c
#include <stdio.h>
#include "linklist.h"
int listmerge();
int main(int argc, char const *argv[])
{
linklist H,R;
int a[]={1,3,5,7,9,243};
int b[]={2,4,8,13};
int i;
H = list_create();
if(H == NULL){
return -1;
}
R = list_create();
if(R == NULL){
return -1;
}
for ( i = 0; i < sizeof(a)/sizeof(int); i++)
{
list_tail_insert(H,a[i]);
}
for ( i = 0; i < sizeof(b)/sizeof(int); i++)
{
list_tail_insert(R,b[i]);
}
list_show(H);
list_show(R);
list_merge(H,R);
list_show(H);
list_free(H);
list_free(R);
return 0;
}