随机生成三十个四则运算算式（包含真分数）

#include<iostream>
#include<cstdlib>
#include<ctime>
using namespace std;
#define random(x) (rand()%x)
int gcd(int a,int b){
    if(b==0)return a;
    else return gcd(b,a%b);
}
int main(){
    int n=30,a,b,i,d,e,s,f,a1,b1,d1,e1;
    char syb;
    srand(time(NULL)); 
    while(n--){
        
        s=random(2);
        a=random(99);a++;
        b=random(99);b++;
        i=random(4);
        if(s){                //处理分数 
            d=random(99);d++;
            e=random(99);e++;
            a%=b,d%=e;        //分母大于分子
            f=gcd(a,b);        //真分数分子分母去除最大公约数 
            a/=f,b/=f;
            f=gcd(d,e);
            d/=f,e/=f;
            a1=a*e,b1=b*e,d1=b*d;
            if(i==0){        //进行加减乘除运算 
                a1+=d1;syb='+';
            }else if(i==1){
                a1-=d1;syb='-';
            }else if(i==2){
                a1=a*d;syb='*';
            }else if(i==3){
                a1=a*e;
                b1=b*d;syb='/';
            }
            f=gcd(abs(a1),b1);
            a1/=f,b1/=f;
            cout<<a<<"/"<<b<<" "<<syb<<" "<<d<<"/"<<e<<" = "<<a1<<"/"<<b1<<endl;
        }else{
            b1=0;
            if(i==0){
                a1=a+b;syb='+';
            }else if(i==1){
                a1=a-b;syb='-';
            }else if(i==2){
                a1=a*b;syb='*';
            }else if(i==3){
                a1=a/b;
                b1=a%b; 
                syb='/';
            }
            cout<<a<<" "<<syb<<" "<<b<<" = "<<a1;
            if(b1)cout<<"+"<<b1<<"/"<<b;
            cout<<endl; 
        }
    }
    return 0;
}