#include <stdio.h>
#include <time.h>
#include <stdlib.h>
void main()
{int add(int a,int b);
 int a,b,N,c,i,p,q;
 for (i=0;i<N;i++)
a=1+rand()%50;
b=1+rand()%50;

c=add(a,b);
scanf("%d,%d",&a,&b);
printf("一共作对%d道题目\n",p);
printf("一共做错%d道题目\n",q);
}
int add(int x,int y)
{int e,g,p,q;
p=0;
q=0;
e=x+y;
printf("%d+%d=%d\n",x,y,e);
printf("请输入您的答案\n");
scanf("%d",&g);
if (e=g);
printf("回答正确\n");
p=p+1;
return  (p);
if (e!=g);

错误太多了都看的累了，直接说什么题目吧！

我的神啊。楼主你的代码完全就是不和逻辑啊。我帮你从写了一下：
#include<stdio.h>
#include<math.h>
#include <time.h>
#include <stdlib.h>

int p=0,q=0;//用全局变量

void main()
{  
    void add(int a,int b);//函数的声明
    int a,b,N,i;
    printf("请输入做题目的次数:");
    scanf("%d",&N);
    srand(time(NULL));//建立随机数的种子
    for(i=0;i<N;i++)
    {
        a=1+rand()%50;
        b=1+rand()%50;
        add(a,b);
    }
    printf("做错的题目数是%d",q);
    printf("\n");
    printf("做对的题目数是%d",p);
    printf("\n");
}

//判断做对与做错的题目的数目
void add(int x,int y)
{   
    int e,g;
    printf("请输入您的答案\n");
    scanf("%d",&g);
    e=x+y;
    printf("%d+%d=%d\n",x,y,e);   
    if (e==g)
    {
        printf("回答正确!\n");
        p++;
    }
    else
    {
        printf("回答错误!\n");
        q++;
    }
}
我是在VC++6.0 上运行的，可以出来结果。你的题目的意思是：随便输入一个数，与随机获取的两个随机数的和做比较吧，如果正确记下次数，错误也是。并且对输入几次也做说明吧。

楼主错误太多,回去看看书吧~~~

#include<stdio.h>
#include<stdlib.h>
#include<time.h>
#define SIZE 10

int add(int a,int b)
{   
    int c;
    c= a+b;
    return c;
}

main()
{
    int add1;
    int add2;
    int counter=0;
    int    a;
    int result;
    char answer;
    int score;
    int i=1;
    int wrong1[11]={0,0,0,0,0,0,0,0,0,0,0};
    int wrong2[11]={0,0,0,0,0,0,0,0,0,0,0};
    int wrong[11]={0,0,0,0,0,0,0,0,0,0,0};

    printf("\tA math test for the year one schoolchildren\n\n");
   
    for(i;i<=SIZE;i++)
        {
            srand(time(NULL));
            add1=rand()%20+1;
            add2=rand()%20+1;
        
            printf("\(%d\)\t\t\t%d+%d=",i,add1,add2);
            scanf("%d",&a);
   
            result=add(add1,add2);

            if(a==result)
            {
                printf("You're right!\n");
                counter++;
            }
            else
            {
                printf("You are wrong!Be careful!\n");
                wrong1[i]=add1;
                wrong2[i]=add2;
                wrong[i]=result;
            }

        }

        printf("\n\n\n");

        for(i=1;i<=SIZE;i++)
        {
            if(wrong1[i]!=0)
            {
                printf("the set of the wrongs:");
                printf("\(%d\)\t\t\t%d+%d=%d\n",i,wrong1[i],wrong2[i],wrong[i]);
            }
            else
                ;
        }

        printf("\n\n");
        score=counter*10;
        printf("The mark you got is %d\n\n",score);
}

提问的话要给出代码的注释，和这个代码要实现的功能。