#include<stdio.h>
#include<stdlib.h>
#include<time.h>
int main()
{
int a,b,numOfQues=0,numOfRight=0;
char inquiry;
srand(time(NULL));
printf("欢迎你来做两位数的加减法\n");
do
{
    int temp=rand()%2;
    a=rand()%100;
    b=rand()%100;
    switch(temp)
    {
    case 0:
        {
        int ans;
        printf("%d+%d=",a,b);
        scanf("%d",&ans);
        if(ans==a+b);
        {
            numOfRight++;
            printf("恭喜！答对了！\n");
        }
        else
        printf("错了");
    }
        break;
    }
    case 1:
        {
            int ans;
            printf("%d-%d=",a,b);
            scanf("%d",&ans);
            if(ans==a-b);
            {
                numOfRight++;
                printf("恭喜！答对了！\n");
            }
            else
                printf("错了\n");
    }
        break;
}
            numOfQues++;
            printf("再来一题吗");
            fflush(stdin);
            inquiry=getchar();
}
while(inquiry==!'n'||inquiry==!'N');
printf("你的答题正确率为%.2lf%%，再见！\n",numOfRight*100./numOfQues);
return 0;
}

if语句后面为啥要有逗号呢

#include<stdio.h>
#include<stdlib.h>
#include<time.h>
int main()
{
    int a,b,numOfQues=0,numOfRight=0;
    char inquiry;
    srand(time(NULL));
    printf("欢迎你来做两位数的加减法\n");
    do
    {
        int temp=rand()%2;
        a=rand()%100;
        b=rand()%100;
        switch(temp)
        {
        case 0:
        {
            int ans;
            printf("%d+%d=",a,b);
            scanf("%d",&ans);
            if(ans==a+b)
            {
                numOfRight++;
                printf("恭喜！答对了！\n");
            }
            else
                printf("错了");
        }
        break;
        case 1:
        {
            int ans;
            printf("%d-%d=",a,b);
            scanf("%d",&ans);
            if(ans==a-b)
            {
                numOfRight++;
                printf("恭喜！答对了！\n");
            }
            else
                printf("错了\n");
        }
        break;
        }
        numOfQues++;
        printf("再来一题吗");
        fflush(stdin);
        inquiry=getchar();
    }
    while(inquiry != 'n' && inquiry != 'N');
    printf("你的答题正确率为%.2lf%%，再见！\n",numOfRight*100./numOfQues);
    return 0;
}

你这不是错在哪一步,而是基本上就没对的

大括号也不配对  自己在仔细阅读一下

我是根据书上某个来编的。

哪本书这么坑爹???