电商专业学习嵌入式软件开发第三十六天

• C第十天

今天一天都在讲链表,下午讲了单项循环链表,而且被同样的题型虐了４遍,这４道题目都是相似,看着也不是很难,毕竟知道解题思路,但就是不能转化成代码表达出来。仿照例题也写不出答案,真的需要好好消化一下链表的内容。

#include <stdio.h>
#include <stdlib.h>
struct student
{
    int data;
    struct student *next;
};
struct student *Create()
{
    int n,i;
    printf("要创建几个节点:");
    scanf("%d",&n);getchar();
    struct student *head=(struct student *)malloc(sizeof(struct student));
    struct student *p=(struct student *)malloc(sizeof(struct student));
    printf("请输入数据:");
    scanf("%d",&p->data);getchar();
    head->next=p;
    for(i=1;i<n;i++)
    {
        struct student *q=(struct student *)malloc(sizeof(struct student));
        printf("请输入数据:");
        scanf("%d",&q->data);getchar();
        p->next=q;
        p=q;
    }
    p->next=NULL;
    return head;
}
struct student *T_insert(struct student *head)
{
    struct student *q=(struct student *)malloc(sizeof(struct student));
    printf("请输入数据:");
    scanf("%d",&q->data);
    q->next=head->next;
    head->next=q;
    return head;
}
struct student *W_insert(struct student *head)
{
    struct student *q=(struct student *)malloc(sizeof(struct student));
    printf("请输入数据:");
    scanf("%d",&q->data);
    struct student *p=head->next;
    while(p->next)
    {
        p=p->next;
    }
    p->next=q;
    q->next=NULL;
    return head;
}
void Print(struct student *head)
{
    struct student *p=head->next;
    while(p)
    {
        printf("%d\n",p->data);
        p=p->next;
    }
}
struct student *Find2(struct student *head)
{
    int data;
    struct student *p=head;
    printf("请输入要查找的值:");
    scanf("%d",&data);
    while(p->next && p->data!=data)
    {
        p=p->next;
    }
    if(p->data==data)
        return p;
    else
    {
        printf("没有找到！\n");
        return NULL;
    }
}
struct student *Delete(struct student *head)
{   struct student *p=head;
    struct student *q=Find2(head);
    if(head->next==q)
    {   head->next=q->next;free(q);
        return head;
    }
    else if(NULL==q->next)
    {   while(p)
        {   p=p->next;
            if(p->next==q)
            {   p->next=NULL;free(q);
                return head;}
            }
    }
    else
    {
        while(p)
        {
            p=p->next;
            if(p->next==q)
            {
                p->next=q->next;
                free(q);
                return head;
            }
        }
    }
}
void main()
{
    struct student *head=Create();
    Print(head);
    head=Delete(head);
    Print(head);
}

练习：输入一行字符串，并以此建立一条链表，一个字符占一个节点，并对该字符串逆序输出
如:abcde
edcba

#include <stdio.h>
#include <stdlib.h>
//确定链节的类型
struct node
{
    char info;
    struct node *next;
};
void main()
{   //创建一条链表
    struct node *head=(struct node *)malloc(sizeof(struct node));
    head->next=NULL;
    char c;
    while((c=getchar())!='\n')
    {//新建节点
        struct node *q=(struct node *)malloc(sizeof(struct node));
        q->info=c;
        //头插
        q->next=head->next;
        head->next=q;
    }
    //打印链表的数据
    struct node *p=head->next;
    while(p)
    {
        putchar(p->info);
        p=p->next;
    }
    putchar('\n');
}

练习：从键盘输入２行字符，并分别按输入时的逆序建立２条链表并分别，然后合并２条链表为１条链表并输出合并后的链表。

#include <stdio.h>
#include <stdlib.h>
//确定链节的类型
struct node
{
    char info;
    struct node *next;
};
struct node *Create()
{   //创建一条链表
    struct node *head=(struct node *)malloc(sizeof(struct node));
    head->next=NULL;
    char c;
    while((c=getchar())!='\n')
    {//新建节点
        struct node *q=(struct node *)malloc(sizeof(struct node));
        q->info=c;
        //头插
        q->next=head->next;
        head->next=q;
    }
    return head;
}
    //打印链表的数据
void Print(struct node *head)
{
    struct node *p=head->next;
    while(p)
    {
        putchar(p->info);
        p=p->next;
    }
    putchar('\n');
}
struct node *Sum(struct node *head1,struct node *head2)
{
    struct node *p=head1->next;
    while(p->next)
    {
        p=p->next;
    }
    p->next=head2->next;
    return head1;
}
void main()
{
    struct node *head1=Create();
    Print(head1);
    struct node *head2=Create();
    Print(head2);
    struct node *head=Sum(head1,head2);
    Print(head);
}

练习：从键盘输入一串字符，并以此建立一条正序的单项循环链表并输出。

#include <stdio.h>
#include <stdlib.h>
//确定链节类型
struct node
{
    char data;
    struct node *next;
};
struct node *Create()
{   //创建一条单向循环链表
    struct node *head=(struct node *)malloc(sizeof(struct node));head->next=head;
    struct node *last=head;//last指向链表的最后一个节点
    char c;
    while((c=getchar())!='\n')
    {
        struct node *q=(struct node *)malloc(sizeof(struct node));
        q->data=c;  last->next=q;   last=q;
    }
    last->next=head;
    return last;
}
void Print(struct node *tail)
{   struct node *p=tail->next->next;
    while(p!=tail->next) //p!=head
    {
        putchar(p->data);p=p->next;
    }
    putchar('\n');
}
void main()
{
    struct node *tail=Create();
    Print(tail);
}

练习：从键盘输入２串字符串，分别创建单向循环链表，然后把２个环合并成一个环并输出。

#include <stdio.h>
#include <stdlib.h>
//确定链节类型
struct node
{
    char data;
    struct node *next;
};
struct node *Create()
{   //创建一条单向循环链表
    struct node *head=(struct node *)malloc(sizeof(struct node));head->next=head;
    struct node *last=head;//last指向链表的最后一个节点
    char c;
    while((c=getchar())!='\n')
    {
        struct node *q=(struct node *)malloc(sizeof(struct node));
        q->data=c;  last->next=q;   last=q;
    }
    last->next=head;
    return last;
}
void Print(struct node *tail)
{   struct node *p=tail->next->next;
    while(p!=tail->next) //p!=head
    {
        putchar(p->data);p=p->next;
    }
    putchar('\n');
}
struct node *Sum(struct node *tail1,struct node *tail2)
{
    struct node *head=tail1->next;
    tail1->next=tail2->next->next;
    tail2->next=head;
    return tail2;
}
void main()
{
    struct node *tail1=Create();
    Print(tail1);
    struct node *tail2=Create();
    Print(tail2);
    struct node *tail=Sum(tail1,tail2);
    Print(tail);
}