链表综合问题PTA,急

Question

本题要求实现多个函数完成对链表的各项基本操作：创建链表，按要求查找，在指定位置添加结点，删除结点，链表排序，输出链表等操作。
链表中为若干个学生的信息（学号、成绩），当输入学号为0时结束；查找并输出不及格的学生信息；新增一个学生信息到指定的学号前面；将指定学号的学生从链表中删除。 将链表中的学生信息按照分数降序排序。

函数接口定义：

Stu * Creatlink( );
void Printlink(Stu * head);
void Search(Stu * head);
Stu *Delnode(Stu * head,int n);
Stu * Addnode(Stu * head,int n);
Stu *Sortnode(Stu * head);

裁判测试程序样例：

#include <stdio.h>
#include <stdlib.h>
#define LEN sizeof(struct stu)
struct stu
{ 
  int num;
  float score;
  struct stu *next;
};
typedef struct stu Stu;

Stu *Creatlink();
void Printlink(Stu *head);
void Search(Stu *head);
Stu *Delnode(Stu *head,int n);
Stu *Addnode(Stu *head,int n);
Stu *Sortnode(Stu *head);

int main()
{ 
       Stu *head = NULL; 
       int num;
       head = Creatlink(); 
       if(head !=NULL)
             Printlink(head);
       else
       { 
        printf("Empty list\n"); 
              return 0;        
       }
       printf("The student no pass:\n"); 
       Search(head);
   
       scanf("%d",&num);
       head=Delnode(head,num);
       if(head !=NULL)
       {
               printf("After delete the student:\n"); 
           Printlink(head);
    }
    else
       { 
        printf("After delete：empty list\n"); 
              return 0;        
       }
   
       scanf("%d",&num);
       head=Addnode(head,num);
       printf("After add the student:\n");
       Printlink(head);
   
       head = Sortnode(head);
       printf("After sorted:\n");
       Printlink(head);
       return 0;
}
/* 请在这里填写答案 */

输入样例：
2,58
3,69
4,98
5,45
6,30
9,80
11,40
0,0
6
9
7,88
输出样例：
2,58
3,69
4,98
5,45
6,30
9,80
11,40
The student no pass:
2,58
5,45
6,30
11,40
After delete the student:
2,58
3,69
4,98
5,45
9,80
11,40
After add the student:
2,58
3,69
4,98
5,45
7,88
9,80
11,40
After sorted:
4,98
7,88
9,80
3,69
2,58
5,45
11,40
代码长度限制
16 KB
时间限制
400 ms
内存限制
64 MB

Answer 1

让阿豪来帮你解答，本回答参考chatgpt3.5编写提供，如果还有疑问可以评论或留言

链表操作函数的代码实现如下：

#include <stdio.h>
#include <stdlib.h>
#define LEN sizeof(struct stu)
struct stu {
    int num;
    float score;
    struct stu* next;
};
typedef struct stu Stu;
Stu* Creatlink();
void Printlink(Stu* head);
void Search(Stu* head);
Stu* Delnode(Stu* head, int n);
Stu* Addnode(Stu* head, int n);
Stu* Sortnode(Stu* head);
// 创建链表
Stu* Creatlink() {
    Stu* head = NULL, * p1 = NULL, * p2 = NULL;
    p1 = (Stu*)malloc(LEN);
    if (p1 == NULL) return NULL;
    head = p2 = p1;
    scanf("%d,%f", &p1->num, &p1->score);
    while (p1->num) {
        p2->next = p1;
        p2 = p1;
        p1 = (Stu*)malloc(LEN);
        scanf("%d,%f", &p1->num, &p1->score);
    }
    p2->next = NULL;
    return head;
}
// 输出链表
void Printlink(Stu* head) {
    Stu* p = head;
    while (p != NULL) {
        printf("%d,%.0f\n", p->num, p->score);
        p = p->next;
    }
}
// 查找不及格的学生
void Search(Stu* head) {
    Stu* p = head;
    int flag = 0;
    while (p != NULL) {
        if (p->score < 60) {
            printf("%d,%.0f\n", p->num, p->score);
            flag = 1;
        }
        p = p->next;
    }
    if (!flag) printf("Not Found\n");
}
// 删除指定学号的学生
Stu* Delnode(Stu* head, int n) {
    Stu* p1 = head, * p2 = head;
    while (p1 != NULL) {
        if (p1->num == n) {
            if (p1 == head)
                head = p1->next;
            else
                p2->next = p1->next;
            free(p1);
            printf("Deleted Successfully\n");
            break;
        }
        p2 = p1;
        p1 = p1->next;
    }
    if (p1 == NULL)
        printf("Not Found\n");
    return head;
}
// 在指定位置添加学生记录
Stu* Addnode(Stu* head, int n) {
    Stu* p1 = head, * p2 = head, * pnew;
    pnew = (Stu*)malloc(LEN);
    pnew->next = NULL;
    scanf("%d,%f", &pnew->num, &pnew->score);
    while (p1 != NULL) {
        if (p1->num == n) {
            if (p1 == head) {
                head = pnew;
                pnew->next = p1;
            }
            else {
                pnew->next = p1;
                p2->next = pnew;
            }
            printf("Added Successfully\n");
            break;
        }
        p2 = p1;
        p1 = p1->next;
    }
    if (p1 == NULL)
        printf("Not Found\n");
    return head;
}
// 按成绩降序排序
Stu* Sortnode(Stu* head) {
    Stu *p, *q, *tail = NULL;
    q = head;
    while (q != tail) {
        p = head;
        while (p->next != tail) {
            if (p->score < p->next->score) {
                int tmp_num = p->num;
                float tmp_score = p->score;
                p->num = p->next->num;
                p->score = p->next->score;
                p->next->num = tmp_num;
                p->next->score = tmp_score;
            }
            p = p->next;
        }
        tail = p;
    }
    return head;
}

主函数中的代码如下：

int main(){
    Stu* head = NULL;
    int num;
    head = Creatlink();
    if (head != NULL)
        Printlink(head);
    else {
        printf("Empty list\n");
        return 0;
    }
    printf("The student no pass:\n");
    Search(head);
    scanf("%d", &num);
    head = Delnode(head, num);
    if (head != NULL)
        Printlink(head);
    else {
        printf("After delete: empty list\n");
        return 0;
    }
    scanf("%d", &num);
    head = Addnode(head, num);
    Printlink(head);
    head = Sortnode(head);
    printf("After sorted:\n");
    Printlink(head);
    return 0;
}