#include <stdio.h>
#include<windows.h>
#include <stdlib.h>
#define LEN sizeof(struct test)
struct test
{
    char que[200];
    char answer1[200];
    char answer2[200];
    char answer3[200];
    char answer4[200];
    char ture;
    struct test *next;
};
void initializelist(struct test *head)
{
    head=(struct test *)malloc(sizeof(struct test));
    head->next=NULL;
}
int zts(struct test *head) //将所有题目导入内存
{
    FILE *fp;
    struct test *p1=NULL;
    char ch1[100];
    int n=0;
    struct test *temp=head;
    if((fp=fopen("test.txt","r"))==NULL)//只读方式打开文件
    {
        printf("文件打开失败请检查test.txt文件。\n");
        exit(0);
    }
   
    for(n=0;!feof(fp);n++){
        temp->next=(struct test *)malloc(sizeof(struct test));
        temp=temp->next;
        temp->next=NULL;
        fscanf(fp,"%s%s%s%s%s%s",temp->que,temp->answer1,temp->answer2,temp->answer3,temp->answer4,ch1);
        temp->ture=ch1[0];
    }
   
    fclose(fp);
    return n;//返回题目总数n
}
void exe1(struct test *head)
{
  void exe2();
  int main();
    int n,m=0,i,tm,t=0,f=0;
    char ans;
    tm=zts(head);        //题目数量
    struct test *temp=head;
    struct test *p1=head->next;
    system("cls");
    printf("请输入要答题数：");
    scanf("%d",&n);
    while(n<0||n>tm){
        printf("输入的答题超过题目数量，或则小于0\n");
        Sleep(1200);
        system("cls");
        printf("请重新输入答题数：");
        scanf("%d",&n);
    }
    for(i=0;i<n;i++)//n为用户要答题数
    {
        printf("\n第%d题：\n",i+1);
        printf("%s\n%s\n%s\n%s\n%s\n请输入答案：",p1->que,p1->answer1,p1->answer2,p1->answer3,p1->answer4);
        while((getchar())!='\n');
        scanf("%c",&ans);
        if(toupper(ans)==p1->ture)//判断用户输入答案是否正确
        {
            printf("恭喜你答对了！\n\n");
            t++;//回答正确统计
        }
        else
        {
            printf("对不起，你答错了。。。\n正确答案是：%c\n\n",p1->ture);
            f++;//回答错误统计
        }
        p1=p1->next;
    }
    p1=head->next;
    do
    {
        head=p1->next;
        free(p1);
        p1=head;
    }while(p1!=NULL);//释放结构体占用内存
    printf("*******************************\n");
    printf("\n已完成测试!\n共做%d道题：%d错误，%d正确。\n正确率：%5.2f%%\n\n",n,f,t,(float)t/n*100);
    printf("*******************************\n");
    printf("\n\n1.继续答题；2.添加题目；3.返回主菜单；\n请选择：");
    i=0;
    scanf("%d",&i);
    if(i==1)
        exe1(temp);//继续答题
    else
        if(i==2)
            exe2();//添加题目
        else
            main();//返回主菜单
}
void exe2()//实现用户自主输入题目
{
    int main();
    system("cls");
    int n;
    FILE *fp;
    if((fp=fopen("test.txt","a"))==NULL)
    {
        printf("文件打开失败请检查test.txt文件。\n");
        exit(0);
    }
    struct test *p1=NULL;
    p1=(struct test *)malloc(LEN);//开辟内存空间
    do
    {
        printf("请输入题目：");
        scanf("%s",&p1->que);
    }while(p1->que[0]=='\0');
    do
    {
        printf("请输入选项A：");
        scanf("%s",&p1->answer1);
    }while(p1->answer1=='\0');
    do
    {
        printf("请输入选项B：");
        scanf("%s",&p1->answer2);
    }while(p1->answer2=='\0');
    do
    {
        printf("请输入选项C：");
        scanf("%s",&p1->answer3);
    }while(p1->answer3=='\0');
    do
    {
        printf("请输入选项D：");
        scanf("%s",&p1->answer4);
    }while(p1->answer4=='\0');
    printf("请输入答案：");
    do
    {
        scanf("%c",&p1->ture);
        p1->ture=toupper(p1->ture);
    }while(p1->ture!='A'&&p1->ture!='B'&&p1->ture!='C'&&p1->ture!='D');
    printf("\n确认输入题目？\n1.是。 2.否。\n");
    scanf("%d",&n);
    if(n==1)
    {
        fputc('\n',fp);
        fputs(p1->que,fp);
        fputc(' ',fp);
        fputs("A.",fp);
        fputs(p1->answer1,fp);
        fputc(' ',fp);
        fputs("B.",fp);
        fputs(p1->answer2,fp);
        fputc(' ',fp);
        fputs("C.",fp);
        fputs(p1->answer3,fp);
        fputc(' ',fp);
        fputs("D.",fp);
        fputs(p1->answer4,fp);
        fputc(' ',fp);
        fputc(p1->ture,fp);
        fclose(fp);
        printf("保存成功!");
        system("cls");
        free(p1);
        printf("是否继续添加？\n1.继续添加  2.返回主菜单\n");
        scanf("%d",&n);
        if(n==1)
            exe2();
        else
            main();
    }
    else
    {
        free(p1);
        exe2();
    }
}
int main()
{
    struct test head;
    system("cls");
    initializelist(&head);
    int n;
    printf("********************************\n");
    printf("欢迎使用单项选择题标准化考试系统\n");
    printf("********************************\n");
    printf("\t1.开始答题。\n");
    printf("\t2.添加试题。\n");
    printf("\t3.退出系统。\n");
    printf("\n请选择：");
    scanf("%d",&n);
    switch(n)
    {
        case 1:exe1(&head);break;
        case 2:exe2();break;
        case 3:printf("\ngoodbye!\n");
    }while(n!=3);
}