实验11-2-2 学生成绩链表处理

#include <stdio.h>
#include <stdlib.h>

struct stud_node {
    int    num;
    char   name[20];
    int    score;
    struct stud_node* next;
};

struct stud_node* createlist();
struct stud_node* deletelist(struct stud_node* head, int min_score);

int main()
{
    int min_score;
    struct stud_node* p, * head = NULL;

    head = createlist();
    scanf_s("%d", &min_score);
    head = deletelist(head, min_score);
    for (p = head; p != NULL; p = p->next)
        printf("%d %s %d
", p->num, p->name, p->score);

    return 0;
}

/* 你的代码将被嵌在这里 */
struct stud_node* createlist()
{
    struct stud_node* head, *tail, *p;
    int num;

    head = tail = NULL;
    scanf_s("%d", &num);
    while (num != 0)
    {
        p = (struct stud_node*)malloc(sizeof(struct stud_node));
        p->num = num;
        scanf_s(" %s %d", p->name,20, &(p->score));
        p->next = NULL;

        if (head == NULL)
        {
            head = p;
            tail = p;
        }
        else
        {
            tail->next = p;
            tail = p;
        }
        
        scanf_s("%d", &num);
    }

    return head;
}
struct stud_node* deletelist(struct stud_node* head, int min_score)
{
    struct stud_node* p, * q;

    while ((head != NULL) && (head->score < min_score))
    {
        p = head;
        head = head->next;
        free(p);
    }

    if (head != NULL)
    {
        q = head;
        p = head->next;

        while (p != NULL)
        {
            if (p->score < min_score)
            {
                q->next = p->next;
                free(p);
                p = q->next;
            }
            else
            {
                q = p;
                p = p->next;
            }
        }
    }

    return head;
}