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

int main() 
{
    srand(time(NULL)); 

    int num1, num2, result, answer,accuracy,correctnum,x;
    char operator;

    correctnum=0;
    for (int i = 0; i < 10; i++) {
        num1 = rand() % 10 + 1; 
        num2 = rand() % 10 + 1;
        operator = rand() % 4; 
        if (operator==0)
        {
            printf("%d + %d = ", num1, num2);
            result = num1 + num2;
        }
        else if (operator==1)
        {
            printf("%d - %d = ", num1, num2);
            result = num1 - num2;
        }
        else if (operator==2)
        {
            printf("%d * %d = ", num1, num2);
            result = num1 * num2;
        }
        else
        {
            while (num1%num2!=0)
            {
                num1 = rand() % 10 + 1; 
                num2 = rand() % 10 + 1;
            }
            printf("%d / %d = ", num1, num2);
            result = num1 / num2;
        }
        scanf("%d", &answer);
        if (answer == result) 
        {
            printf("回答正确！\n");
            correctnum++;
        } 
        else 
        {
            printf("回答错误！正确答案是：%d\n", result);
        }
        sleep(1); 
        system("cls");
        //getchar(); 
    }
    accuracy=correctnum*10;
    printf("小朋友你的得分为：%d\n",accuracy);
    return 0;
}

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

// 定义学生结构体
typedef struct Student {
    char sno[5];       // 学号
    char sname[10];    // 姓名
    int score;         // 分数
    struct Student *rear; // 指向下一个学生节点的指针
} Student;

// 创建一个新学生节点
Student* createStudent(const char* sno, const char* sname, int score) 
{
    Student* newStudent = (Student*)malloc(sizeof(Student));
    if (newStudent) 
    {
        strncpy((*newStudent).sno, sno, 5);   // 设置学号
        strncpy((*newStudent).sname, sname, 10); // 设置姓名
        (*newStudent).score = score;          // 设置分数
        (*newStudent).rear = NULL;            // 设置下一个节点指针为空
    }
    return newStudent; // 返回新创建的学生节点
}

// 将新学生插入到链表中，保持链表按分数降序排列
Student* insertStudent(Student* head, Student* newStudent) 
{
    // 如果链表为空或新学生分数高于头节点分数，插入到头部
    if (head == NULL || (*newStudent).score > (*head).score) 
    {
        (*newStudent).rear = head;
        return newStudent;
    }

    // 否则找到合适的插入位置
    Student* current = head;
    while ((*current).rear != NULL && (*((*current).rear)).score > (*newStudent).score) 
    {
        current = (*current).rear;
    }

    // 插入新学生
    (*newStudent).rear = (*current).rear;
    (*current).rear = newStudent;
    return head; // 返回链表头部指针
}

// 打印整个链表
void printList(Student* head) {
    Student* current = head;
    while (current != NULL) 
    {
        printf("%s %s %d\n", (*current).sno, (*current).sname, (*current).score);
        current = (*current).rear;
    }
}

// 根据学号删除学生
Student* deleteStudent(Student* head, const char* sno) {
    Student* current = head;
    Student* previous = NULL;
    
    // 遍历找到要删除的学生节点
    while (current != NULL && strcmp((*current).sno, sno) != 0) 
    {
        previous = current;
        current = (*current).rear;
    }

    // 如果找不到，返回原链表
    if (current == NULL) return head;

    // 如果删除的是头节点
    if (previous == NULL) 
    {
        head = (*current).rear;
    } 
    else // 删除的是中间或尾节点
    {
        (*previous).rear = (*current).rear;
    }

    free(current); 
    return head; // 返回链表头部指针
}

int main() {
    Student* head = NULL;
    // 创建并插入几个学生节点
    head = insertStudent(head, createStudent("1001", "学生甲", 95));
    head = insertStudent(head, createStudent("1002", "学生乙", 75));
    head = insertStudent(head, createStudent("1003", "学生丙", 83));
    head = insertStudent(head, createStudent("1004", "学生丁", 93));
    head = insertStudent(head, createStudent("1005", "学生戊", 80));

    printf("初始链表:\n");
    printList(head); // 打印初始链表

    head = deleteStudent(head, "1003"); 

    printf("删除后的链表:\n");
    printList(head); // 打印删除后的链表

    while (head != NULL) {
        Student* temp = head;
        head = (*head).rear;
        free(temp);
    }

    return 0;
}