本次作业要求：（1）出题器可以随机出四则运算。（2）真分数的运算。以下为程序运行截图：
根据使用说明来输入整数题目的数量，以及分数题目的数量，这里分别以5道题为例。
如果回答正确就会提示“回答正确”，回答错误则会提示“回答错误”。所有题目全部回答完毕将会给出得分情况。
为了便于打印，将所有的算术题存到了文本中。
以上为该程序的内容和使用详情，以下为程序源代码：
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
int add(int);
int sub(int);
int mult(int);
int divi(int);
int max(int,int);
int gys(int,int);
int main()
{
FILE *fp;fp=fopen("count.txt","a+");
srand((unsigned)(time(NULL)));
int i,m,n;int answer,t,right=0,score=0;
printf("\t\t\t\t\t欢迎使用小学四则运算出题器\n使用说明：请根据提示输入题目的数量，需要多少道分数题。\n\t 整数除法题目如果存在余数请输入余数。\n\t 真分数计算题的答案先输入分子再输入分母。");
printf("\n请输出整数题目数量：\n");
scanf("%d",&n);
printf("\n请输入分数题目数量:\n");
scanf("%d",&t);
for(m=0;m<n;m++) //整数计算
{
i=rand()%4+1;
switch(i)
{
case 1:answer=add(1);
if(answer==1){right++;score=score+10;printf("回答正确\n");}else printf("回答错误\n");break;
case 2:answer=sub(1);
if(answer==1){right++;score=score+10;printf("回答正确\n");}else printf("回答错误\n");break;
case 3:answer=mult(1);
if(answer==1){right++;score=score+10;printf("回答正确\n");}else printf("回答错误\n");break;
case 4:answer=divi(1);
if(answer==1){right++;score=score+10;printf("回答正确\n");}else printf("回答错误\n");break;
}
}
for(m=0;m<t;m++) //分数计算
{
i=rand()%4+1;
switch(i)
{
case 1:answer=add(2);
if(answer==1){right++;score=score+10;printf("回答正确\n");}else printf("回答错误\n");
break;
case 2:answer=sub(2);
if(answer==1){right++;score=score+10;printf("回答正确\n");}else printf("回答错误\n");break;
case 3:answer=mult(2);
if(answer==1){right++;score=score+10;printf("回答正确\n");}else printf("回答错误\n");break;
case 4:answer=divi(2);
if(answer==1){right++;score=score+10;printf("回答正确\n");}else printf("回答错误\n");break;
}
}
printf("共有%d道题，答对%d道，总得分：%d\n",n+t,right,score); //输出
fclose(fp);
return 0;
}
int max(int a,int b){if(a>=b)return a;else return b;} //求最大值
int gys(int a,int b){if(a%b)return gys(b,a%b);return b;} //求最大公约数
int add(int q){ FILE *fp;fp=fopen("count.txt","a+"); //加法
if(q==1){
srand((unsigned)(time(NULL)));
int a=rand()%100+1,b=rand()%100+1;int answer;
printf("%d + %d =",a,b);
fprintf(fp,"%d + %d =\n",a,b);
scanf("%d",&answer);
if(a+b==answer){return 1;}else return 0;}
if(q==2){
int e,f,x,y,z,x1,x2,x3,x4,a=rand()%15+1,b=rand()%13+1,c=rand()%13+1,d=rand()%15+1;
srand((unsigned)(time(NULL)));
x1=a+b-max(a,b);x2=max(a,b);x3=c+d-max(c,d);x4=max(c,d);
x=gys(x1,x2);x1=x1/x;x2=x2/x;x=gys(x3,x4);x3=x3/x;x4=x4/x;
printf("%d/%d + %d/%d =",x1,x2,x3,x4);
fprintf(fp,"%d/%d + %d/%d =\n",x1,x2,x3,x4);
scanf("%d",&e);scanf("%d",&f); //e为分子，f为分母
y=(x2*x4)/gys(x2,x4); //同分分母 y
x=(x1)*y/x2+(x3)*y/x4; //同分分子 x
z=gys(x,y);
if(z==1){if(x==e&&y==f)return 1;else return 0;}else if(x/z==e&&y/z==f)return 1;else return 0;
}
}
int sub(int q){int p;FILE *fp;fp=fopen("count.txt","a+");
if(q==1){
srand((unsigned)(time(NULL)));
int a=rand()%100+1,b=rand()%100+1;int answer;
if(a>b){printf("%d - %d =",a,b);}
else {p=a;a=b;b=p;{printf("%d - %d =",a,b);}}
fprintf(fp,"%d - %d =\n",a,b);
scanf("%d",&answer);
if(a-b==answer){return 1;}else return 0;}
if(q==2)
{
int e,f,x,y,z,x1,x2,x3,x4,a=rand()%15+1,b=rand()%15+1,c=rand()%15+1,d=rand()%15+1;
srand((unsigned)(time(NULL)));
x1=a+b-max(a,b);x2=max(a,b);x3=c+d-max(c,d);x4=max(c,d); //x1是被减数分子，x2被减数分母，x3减数分子，x4减数分母
x=gys(x1,x2);x1=x1/x;x2=x2/x;x=gys(x3,x4);x3=x3/x;x4=x4/x;
x=gys(x2,x4);y=x1*x4/x;z=x3*x2/x;
if(y-z<0){x=x1;x1=x3;x3=x;x=x2;x2=x4;x4=x;}
printf("%d/%d - %d/%d =",x1,x2,x3,x4);
fprintf(fp,"%d/%d - %d/%d =\n",x1,x2,x3,x4);
scanf("%d",&e);scanf("%d",&f); //e为分子，f为分母
y=(x2*x4)/gys(x2,x4); //通分分母 y
x=(x1)*y/x2-(x3)*y/x4; //通分分子 x
z=gys(x,y);
if(z==1){if(x==e&&y==f)return 1;else return 0;}else if(x/z==e&&y/z==f)return 1;else return 0;
}
}
int mult(int q)
{FILE *fp;fp=fopen("count.txt","a+");
if(q==1){
srand((unsigned)(time(NULL)));
int a=rand()%60+1,b=rand()%60+1;int answer;
printf("%d * %d =",a,b);
fprintf(fp,"%d * %d =\n",a,b);
scanf("%d",&answer);
if(a*b==answer)return 1;else return 0;}
if(q==2){
int e,f,x,y,z,x1,x2,x3,x4,a=rand()%15+1,b=rand()%15+1,c=rand()%15+1,d=rand()%15+1;
srand((unsigned)(time(NULL)));
x1=a+b-max(a,b);x2=max(a,b);x3=c+d-max(c,d);x4=max(c,d); //x1是被乘数分子，x2被乘数分母，x3乘数分子，x4乘数分母
x=gys(x1,x2);x1=x1/x;x2=x2/x;x=gys(x3,x4);x3=x3/x;x4=x4/x;
printf("%d/%d * %d/%d =",x1,x2,x3,x4);
fprintf(fp,"%d/%d * %d/%d =\n",x1,x2,x3,x4);
scanf("%d",&e);scanf("%d",&f); //e为分子，f为分母
y=x2*x4; //通分分母 y
x=x1*x3; //通分分子 x
z=gys(x,y);
if(z==1){if(x==e&&y==f)return 1;else return 0;}else if(x/z==e&&y/z==f)return 1;else return 0;
}
}
int divi(int q){FILE *fp;fp=fopen("count.txt","a+");
if(q==1){
srand((unsigned)(time(NULL)));
int a=rand()%40+1,b=rand()%20+1;int answer,re;
printf("%d / %d =",a,b);
fprintf(fp,"%d / %d =\n",a,b);
if(a%b==0){
scanf("%d",&answer);
if(a/b==answer)return 1;else return 0;}
else {scanf("%d",&answer);printf("余数为：");scanf("%d",&re); if(a/b==answer&&a%b==re)return 1;else return 0;}
}
if(q==2){
int e,f,x,y,z,x1,x2,x3,x4,a=rand()%15+1,b=rand()%15+1,c=rand()%15+1,d=rand()%15+1;
srand((unsigned)(time(NULL)));
x1=a+b-max(a,b);x2=max(a,b);x3=c+d-max(c,d);x4=max(c,d); //x1是被乘数分子，x2被乘数分母，x3乘数分子，x4乘数分母
x=gys(x1,x2);x1=x1/x;x2=x2/x;x=gys(x3,x4);x3=x3/x;x4=x4/x;
printf("(%d/%d) / (%d/%d) =",x1,x2,x3,x4);
fprintf(fp,"(%d/%d) / (%d/%d) =\n",x1,x2,x3,x4);
scanf("%d",&e);scanf("%d",&f); //e为分子，f为分母
y=x2*x3; //通分分母 y
x=x1*x4; //通分分子 x
z=gys(x,y);
if(z==1){if(x==e&&y==f)return 1;else return 0;}else if(x/z==e&&y/z==f)return 1;else return 0;
}
}