双向链表基本操作

header.h头文件

#include<stdio.h>
#include<stdlib.h>
#include<time.h>
#define N 10
typedef struct node
{
    int key;
    struct node* next;
    struct node* prior;
}DL;
DL* init();//初始化
void creat_link(DL* h);//创建链表
void print(DL* h);//打印
DL * get_Node(DL *h);
DL * get_Nodepos(DL *h,int pos);
DL* insert_val(int val);
void delet_pos(DL *h);
void delet_val(DL *h);
void insert_head(DL * h);
void insert_end(DL *h);
void insert_pos(DL* h);
void search( DL*h);

function.c文件

#include"header.h"
DL* init()
{
    //创建头节点
    DL* h = (DL*)malloc(sizeof(DL));
    h->next = NULL;
    h->prior = NULL;
    return h;
}
DL* create_node()
{
    DL *p;
    p = (DL*)malloc(sizeof(DL));
    if(p == NULL)
    {
        printf("动态内存分配失败！\n");
        exit(0);
    }
    
       p->key = rand()%101;
    p->prior = NULL;
    p->next = NULL;
    return (p);
} 

DL* insert_val(int val)
{
    DL *p;
    p = (DL*)malloc(sizeof(DL));
    if(p == NULL)
    {
        printf("动态内存分配失败！\n");
        exit(0);
    }
    
       p->key =val;
    p->prior = NULL;
    p->next = NULL;
    return (p);
} 

void creat_link(DL* h)
{
    DL * p,* newnode;
    int i =0;
    p = h;
    //带头结点的尾插法
    srand((unsigned)time(NULL));
    while(i<N)
    {
        newnode = create_node();
        p->next = newnode;
        newnode->prior = p;
        p = newnode;
        i++;
    }
}

DL * get_Node(DL *h)
{
    int i = 0,count = 1;
    DL* p = h->next;
    printf("请输入要获取第几个节点的元素\n");
    scanf("%d",&i);
    while(p)
    {
        if(count == i)
        {
            printf("%-5d",p->key);
            break;
        }
        else
        {
            count++;
            p = p->next;
        }            
    }
    return p;
}

DL * get_Nodepos(DL *h,int pos)
{
    int i = 0,count = 1;
    DL* p = h->next;

    while(p)
    {
        if(count == pos)
        {
            printf("%-5d",p->key);
            break;
        }
        else
        {
            count++;
            p = p->next;
        }            
    }
    return p;
}


//删除指定位置的元素
void delet_pos(DL *h)
{
    int pos;
    DL* p = h->next;
    DL * pre;
    int count = 1;
    printf("请输入要删除节点的位置\n");
    scanf("%d",&pos);
    while(pos != count)
    {
        p = p->next;
        count++;
    }
    pre = p->prior;
    pre->next = p->next;
    p->next->prior = pre;
    free(p);
}


void delet_val(DL *h)
{
    int val;
    DL* p = h->next;
    DL * pre;
    printf("请输入要删除的值\n");
    scanf("%d",&val);

    while(p)
    {
        if(val == p->key)
            break;
        else
        p = p->next;
    }
    if(p ==NULL)
        printf("没有找到这个元素\n");
    else
    {
        pre = p->prior;
        pre->next = p->next;
        p->next->prior = pre;
        free(p);
    }
    
}

void insert_head(DL *h)
{
    int val;
    DL* p = h->next;
    DL * newnode;
    printf("请输入插入的值\n");
    scanf("%d",&val);
    newnode = insert_val(val);
    
    newnode->next = h->next;
    p->prior = newnode;
    newnode->prior = h;
    h->next = newnode;

}
void insert_end(DL *h)
{
    int val;
    DL* p = h->next;
    DL * newnode;
    printf("请输入插入的值\n");
    scanf("%d",&val);
    newnode = insert_val(val);
    while(p->next)
        p = p->next;

    p->next = newnode;
    newnode->prior = p;

}

void insert_pos(DL *h)
{
    int val,pos;
    DL* p = h->next,*insert;
    DL * newnode;
    printf("请输入插入的值\n");
    scanf("%d",&val);
    printf("请输入插入的位置\n");
    scanf("%d",&pos);
    insert  = get_Nodepos(h,pos);
    newnode = insert_val(val);

    if(pos == 1)
    {
        newnode->next = h->next;
        p->prior = newnode;
        newnode->prior = h;
        h->next = newnode;
    }
    else
    {
        insert->prior->next = newnode;
        newnode->prior = insert->prior;
        newnode->next = insert;
        insert->prior = newnode; 
    }

}

void search(DL* h)
{
    int val;
    DL* p = h->next;
    printf("请输入查询的值\n");
    scanf("%d",&val);
    while(p)
    {
        if(p->key == val)
            break;
        else
            p = p->next;
    }
    if(p)
        printf("Find it\n");
    else
        printf("NOT EXIST\n");
}

void print(DL* h)
{
    DL*p =h->next;
    printf("链表是:");
    while(p)
    {
        printf("%-5d",p->key);
        p = p->next;
    }
}

 

main.c文件

#include"header.h"
void main()
{
    DL*h = init();
    int choice;
    while(1)
    {
        choice = 0;
        printf("\n\n\n\n\n\n\n\n");
        printf("========================================================================\n");
        printf("按提示输入您的操作\n");
        printf("1:初始化线性表\n");
        printf("2:输出链表\n");
        printf("3:取链表中第i个元素的键值\n");
        printf("4:删除指定位置的元素\n");
        printf("5:删除指定键值的元素\n");
        printf("6:表头添加键值为key的元素\n");
        printf("7:表尾添加键值为key的元素\n");
        printf("8:向表中指定的位置POS处添加键值为key的元素\n");
        printf("9:搜索键值为key的元素,判断是否存在\n");
        printf("输入999退出\n");
        printf("========================================================================\n");

        printf("请输入你的操作:");
        scanf("%d",&choice);
        if(choice==999)
            break;
        switch(choice)
        {
            case 1:system("cls");creat_link(h);break;
            case 2:system("cls");print(h);break;
            case 3:system("cls");get_Node(h);break;
            case 4:delet_pos(h);break;
            case 5:delet_val(h);break;
            case 6:insert_head(h);break;
            case 7:insert_end(h);break;
            case 8:insert_pos(h);break;
            case 9:search(h);break;
            default:break;
        }
        
    }
}