2019年7月30日星期二（数据结构）例题代码

//练习2： 在练习1基础上添加通过电话号码搜索，注销用户。
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

struct list_node{
    char name[20]; //姓名
    int age; //年龄
    char tel[20]; //电话
    struct list_node *next; //指向下一个结构体的地址
};

struct list_node *init_list(struct list_node *head) //head = NULL
{
    head = (struct list_node *)malloc(sizeof(struct list_node));
    if(head == NULL)
        printf("malloc head error!\n");
    head->next = NULL;
    return head;
}

int tail_add_list(struct list_node *head,char *name_buf,int age_buf,char *tel_buf)
{
    struct list_node *Node = NULL;
    Node = (struct list_node *)malloc(sizeof(struct list_node));
    if(Node == NULL)
        printf("malloc Node error!\n");
    strcpy(Node->name,name_buf);
    Node->age = age_buf;
    strcpy(Node->tel,tel_buf);
    Node->next = NULL;
    struct list_node *p = NULL;
    for(p=head;p->next!=NULL;p=p->next);
    p->next = Node;
    return 0;
}

void register_fun(struct list_node *head)
{
    char name_buf[20] = {0};
    int age_buf;
    char tel_buf[20] = {0};
    
    printf("pls input your name:");
    scanf("%s",name_buf);
    printf("pls input your age:");
    scanf("%d",&age_buf);
    printf("pls input your tel:");
    scanf("%s",tel_buf);
    tail_add_list(head,name_buf,age_buf,tel_buf);
    return;
}

void show_fun(struct list_node *head)
{
    struct list_node *p = NULL;
    for(p=head->next;p!=NULL;p=p->next)
    {
        printf("====================\n");
        printf("name = %s\n",p->name);
        printf("age = %d\n",p->age);
        printf("tel = %s\n",p->tel);
    }
    return;
}

int cancel_fun(struct list_node *head)
{
    char cancel_buf[20] = {0};
    printf("pls input cancel tel:");
    scanf("%s",cancel_buf);
    struct list_node *p = NULL;
    struct list_node *q = NULL;
    for(q=head,p=head->next;p!=NULL;q=p,p=p->next)
    {
        if(strcmp(p->tel,cancel_buf) == 0)
        {
            q->next=p->next;
            free(p);
        }
    }
    return 0;    
}

void show_node(struct list_node *p)
{
    printf("name = %s\n",p->name);
    printf("age = %d\n",p->age);
    printf("tel = %s\n",p->tel);
    return;
}

int search_fun(struct list_node *head)
{
    char name_buf[20] = {0};
    printf("pls input search name:");
    scanf("%s",name_buf);
    struct list_node *p = NULL;
    for(p=head->next;p!=NULL;p=p->next)
    {
        if(strcmp(p->name,name_buf) == 0)
        {
            show_node(p);
        }
    }
    
    return 0;
}

int main(int argc,char *argv[])
{
    //1. 初始化链表
    struct list_node *head = NULL;
    head = init_list(head);
    //2. 显示主界面
    int choice;
    while(1)
    {
        printf("================================\n");
        printf("            1. register         \n");
        printf("            2. show                \n");
        printf("            3. exit                \n");
        printf("            4. cancel            \n");
        printf("            5. search            \n");
        printf("================================\n");
        printf("pls input your choice:");
        scanf("%d",&choice);
        switch(choice)
        {
            case 1:
                register_fun(head);
                break;
            case 2:
                show_fun(head);
                break;
            case 3:
                return -1;
                break;
            case 4:
                cancel_fun(head);
                break;
            case 5:
                search_fun(head);
                break;
            default:
                printf("error!\n");
                break;
        }
    }
    return 0;
}
 // 练习3： 在一个目录下有几张BMP格式图片，点击屏幕任意位置，切换到下一张图
//片，实现单向链表完成。
   #include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <dirent.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <linux/input.h>
#include <strings.h>


int show_bmp(char *pname)
{
    char bmp_buf[800*480*3];//BMP格式图片缓冲区
    char lcd_buf[800*480*4];//LCD液晶缓冲区
    char show_buf[800*480*4];
    
    int ret,lcd;
    int i,j,x,y;
    
    //1. 访问BMP图片
    FILE *fp = fopen(pname,"r");
    if(fp == NULL)
        printf("fopen error!\n");
    
    //2. 跳过BMP图片的54个头数据
    ret = fseek(fp,54,SEEK_SET);
    if(ret != 0)
        printf("fseek error!\n");
    
    //3. 读取BMP图片的数据
    ret = fread(bmp_buf,sizeof(bmp_buf),1,fp);
    if(ret != 1)
        printf("fread error!\n");
    
    //4. 访问LCD液晶
    lcd = open("/dev/fb0",O_WRONLY);
    if(lcd < 0)
        printf("open error!\n");
    
    //5. 像素点赋值
    for(i=0,j=0;i<800*480*4;i+=4,j+=3)
    {
        lcd_buf[i] = bmp_buf[j];
        lcd_buf[i+1] = bmp_buf[j+1];
        lcd_buf[i+2] = bmp_buf[j+2];
        lcd_buf[i+3] = 0;
    }
    
    //6. 上下翻转
    for(y=0;y<480;y++)
    {
        for(x=0;x<800*4;x++)
        {
            show_buf[(479-y)*800*4+x] = lcd_buf[y*800*4+x];
        }
    }
    
    //7. 将图片数据写入到LCD液晶屏幕上
    ret = write(lcd,show_buf,sizeof(show_buf));
    if(ret != sizeof(show_buf))
        printf("write error!\n");
    
    //8. 关闭设备与文件
    close(lcd);
    fclose(fp);
    
    return 0;
}


struct list_node{
    char picname[50];
    struct list_node *next;
};

struct list_node *init_list(struct list_node *head) //head = NULL
{
    head = (struct list_node *)malloc(sizeof(struct list_node));
    if(head == NULL)
        printf("malloc head error!\n");
    
    head->next = NULL;
    
    return head;
}

int tail_add_list(struct list_node *head,char *picname)
{
    struct list_node *Node = NULL;
    Node = (struct list_node *)malloc(sizeof(struct list_node));
    if(Node == NULL)
        printf("Node malloc error!\n");
    
    strcpy(Node->picname,picname);
    Node->next = NULL;
    
    struct list_node *p = NULL;
    for(p=head;p->next!=NULL;p=p->next);
    
    p->next = Node;
    
    return 0;
}

int touch_fun(struct list_node *head)
{
    int fd;
    struct input_event buf;
    int x;
    struct list_node *p = NULL;
    p=head->next;
    
    //9. 读取触摸屏数据
    while(1)
    {
        fd = open("/dev/input/event0",O_RDONLY);
        if(fd < 0)
            printf("open ts error!\n");
        bzero(&buf,sizeof(buf));
        read(fd,&buf,sizeof(buf));
        if(buf.type == EV_KEY && buf.code == BTN_TOUCH && buf.value == 0);
        for(;p!=NULL;)
        {    
            show_bmp(p->picname);
            printf("%s\n",p->picname);
            p=p->next;
            break;
        }
        if(p==NULL)
                break;
        close(fd);
    }
    
    return 0;
}

int delete_list(struct list_node *head)
{
    struct list_node *p = NULL;
    struct list_node *q = NULL;
    
    for(p=q=head;p!=NULL;p=q)
    {
        q=p->next;
        free(p);
    }
    
    return 0;
}

int main(int argc,char *argv[])
{
    //0. 初始化链表
    struct list_node *head = NULL;
    head = init_list(head);
    
    //1. 打开目录
    DIR *dp = opendir("./pic/");
    if(dp == NULL)
        printf("opendir error!\n");
    
    //2. 切换目录
    chdir("./pic/");
    
    //3. 读取目录中内容
    struct dirent *ep = NULL;
    while(1)
    {
        ep = readdir(dp);
        if(ep == NULL)
            break;
        
        if(ep->d_name[0] == '.')
            continue;
        
        tail_add_list(head,ep->d_name);
    }
    show_bmp(head->next->picname);
    touch_fun(head);
    delete_list(head);
    return 0;
}
//练习4： 完成单向循环链表接口。
#include <stdio.h>
#include <stdlib.h>

//设计节点模型
struct list_node{
    int a;
    struct list_node *next;
};

struct list_node *init_list_head(struct list_node *head) //head = NULL
{
    //为头节点申请空间
    head = (struct list_node *)malloc(sizeof(struct list_node));
    if(head == NULL)
        printf("head malloc error!\n");
    
    //为头节点的指针域赋值
    head->next = head;
    
    return head;
}

int tail_add_list(struct list_node *head,int num)
{
    //为新节点申请空间
    struct list_node *Node = NULL;
    Node = (struct list_node *)malloc(sizeof(struct list_node));
    
    //为新节点赋值
    Node->a = num;
    Node->next = head;
    
    //寻找最后一个节点，并尾插
    struct list_node *p = NULL;
    for(p=head;p->next!=head;p=p->next); 
    //从循环出来时，p->next=NULL，也就是说，p指向最后一个节点！
    
    p->next = Node;
    
    return 0;
}

int show_list_node(struct list_node *head)
{
    struct list_node *p = NULL;
    for(p=head->next;p!=head;p=p->next)
    {
        printf("%d\n",p->a);
    }
    
    return 0;
}

int head_add_list(struct list_node *head,int num)
{
    struct list_node *Node = NULL;
    Node = (struct list_node *)malloc(sizeof(struct list_node));
    struct list_node *p = NULL;
    struct list_node *q = NULL;
    for(q=head,p=head->next;p!=head;q=p,p=p->next)
    {    
        Node->a = num;
        Node->next = p;
        q->next = Node;
    }
    
    return 0;
}

void show_node(struct list_node *p)
{
    printf("p->a = %d\n",p->a);
    return ;
}

int search_list_node(struct list_node *head,int num)
{
    struct list_node *p = NULL;
    for(p=head;p->next!=head;p=p->next)
    {
        if(p->a == num)
        {
            show_node(p);  
            return 0;
        }
    }
    
    printf("Not Found:%d\n",num);
    return -1;
}

int delete_list_node(struct list_node *head,int num)
{
    struct list_node *p = NULL;
    struct list_node *q = NULL;
    
    for(q=head,p=head->next;p!=head;q=p,p=p->next)
    {
        if(p->a == num)
        {
            q->next = p->next;
            free(p);
            return 0;
        }
    }
    
    return -1;
}

int delete_list(struct list_node *head)
{
    struct list_node *p = NULL;
    struct list_node *q = NULL;
    for(q=head,p=head->next;p!=head;q=p,p=p->next);
        q->next=NULL;
    for(q=head,p=head->next;p!=NULL;q=p,p=p->next)
    {
        q=p->next;
        free(p);
    }
    
    return 0;
}

int main(int argc,char *argv[])
{
    //1. 初始化链表头
    struct list_node *head = NULL;
    head = init_list_head(head);
    
    //2. 尾插数据
    tail_add_list(head,10);
    tail_add_list(head,20);
    tail_add_list(head,30);
    tail_add_list(head,40);
    
    //3. 头插数据
    head_add_list(head,8);
    head_add_list(head,5);
    head_add_list(head,3);
    
    //4. 遍历链表
    //show_list_node(head);
    
    //5. 根据特征值来寻找节点
    search_list_node(head,30);
    
    //6. 根据特征值删除节点
    delete_list_node(head,8);
    
    //7. 遍历链表
    show_list_node(head);
    
    //8. 释放整条链表的内存空间
    delete_list(head);
    
    return 0;
}
  //练习5： 使用单向循环链表完成练习3，要求点击最后一张回到第一张。
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <dirent.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
#include <linux/input.h>
#include <strings.h>

struct list_node{
    char picname[20];
    struct list_node *next;
};

struct list_node *init_list_head(struct list_node *head)
{
    head = (struct list_node *)malloc(sizeof(struct list_node));
    if(head == NULL)
        printf("malloc head error!\n");
    
    head->next = head;
    
    return head;
}

int tail_add_list(struct list_node *head,char *picname)
{
    struct list_node *Node = NULL;
    Node = (struct list_node *)malloc(sizeof(struct list_node));
    if(Node == NULL)
        printf("malloc Node error!\n");
    
    strcpy(Node->picname,picname);
    Node->next = head;
    
    struct list_node *p = NULL;
    for(p=head;p->next!=head;p=p->next);  //p->next=head
    
    p->next = Node;
    
    return 0;
}

void show_bmp(char *name)
{
    char bmp_buf[800*480*3];//BMP格式图片缓冲区
    char lcd_buf[800*480*4];//LCD液晶缓冲区
    char show_buf[800*480*4];
    
    int ret,lcd;
    int i,j,x,y;
    
    //1. 访问BMP图片
    FILE *fp = fopen(name,"r");
    if(fp == NULL)
        printf("fopen error!\n");
    
    //2. 跳过BMP图片的54个头数据
    ret = fseek(fp,54,SEEK_SET);
    if(ret != 0)
        printf("fseek error!\n");
    
    //3. 读取BMP图片的数据
    ret = fread(bmp_buf,sizeof(bmp_buf),1,fp);
    if(ret != 1)
        printf("fread error!\n");
    
    //4. 访问LCD液晶
    lcd = open("/dev/fb0",O_WRONLY);
    if(lcd < 0)
        printf("open error!\n");
    
    //5. 像素点赋值
    for(i=0,j=0;i<800*480*4;i+=4,j+=3)
    {
        lcd_buf[i] = bmp_buf[j];
        lcd_buf[i+1] = bmp_buf[j+1];
        lcd_buf[i+2] = bmp_buf[j+2];
        lcd_buf[i+3] = 0;
    }
    
    //6. 上下翻转
    for(y=0;y<480;y++)
    {
        for(x=0;x<800*4;x++)
        {
            show_buf[(479-y)*800*4+x] = lcd_buf[y*800*4+x];
        }
    }
    
    //7. 将图片数据写入到LCD液晶屏幕上
    ret = write(lcd,show_buf,sizeof(show_buf));
    if(ret != sizeof(show_buf))
        printf("write error!\n");
    
    //8. 关闭设备与文件
    close(lcd);
    fclose(fp);
}

int main(int argc,char *argv[])
{
    //0. 初始化链表
    struct list_node *head = NULL;
    head = init_list_head(head);
    
    //1. 打开目录
    DIR *dp = opendir("./pic/");
    if(dp == NULL)
        printf("opendir error!\n");
    
    //2. 切换目录
    chdir("./pic/");
    
    //3. 读取目录中内容
    struct dirent *ep = NULL;
    while(1)
    {
        ep = readdir(dp);
        if(ep == NULL)
            break;
        
        if(ep->d_name[0] == '.')
            continue;
        
        tail_add_list(head,ep->d_name);
    }
    
    //4. 显示第一张图片
    struct list_node *p = head->next;
    show_bmp(p->picname);
    
    //5. 访问触摸屏设备
    int fd = open("/dev/input/event0",O_RDONLY);
    if(fd < 0)
        printf("open event0 error!\n");
    
    //6. 不断读取触摸屏数据
    struct input_event buf;
    while(1)
    {
        bzero(&buf,sizeof(buf));
        read(fd,&buf,sizeof(buf));
        if(buf.type == EV_KEY && buf.code == BTN_TOUCH && buf.value == 0)
        {
            p=p->next;
            if(p==head)
            {
                p=p->next;
            }
            show_bmp(p->picname);
        }
    }
    close(fd);
    closedir(dp);
    return 0;
}