软工 个人项目二

这次作业的主要内容是第二个博客的续写，在产生30道整数四则运算的基础上加上真分数形式的四则运算。程序是在第二个博客基础上加上对分子，分母的限制。从而生成可用真分数。

 #include <iostream> 
#include <stdlib.h>
#include <time.h>
using namespace std;
int main()
{
    int a, b, c, d, i, j;
    srand((unsigned)time(NULL));
    for (j = 30; j > 0; j--)
    { 
        char operator_lib[4] = { '+', '*', '/', '-' }; //定义运算符的可选类型
        int rand_oper_idx = rand() % 4; //然后随机生成，上述数组的下标就可以了。
        char cur_oper = operator_lib[rand_oper_idx];
        i = rand() % 2; 
        switch (i)
        {
        case 0:
            a = rand() % 100; //a取值为0~99 
            c = rand() % 100; //c取值为1~99
            if (cur_oper == '/')
            { 
                if (c == 0)
                { 
                    c = rand() % 99+1;
                } 
                cout << a << cur_oper << c << " = " << endl;
            } 
            else 
                cout << a << cur_oper << c << " = " << endl;
            break;
        case 1: 
            a = rand() % 99 + 1; //a取值为1~99
            b = rand() % a; //保证b小于a
            c = rand() % 99 + 1; //c取值1~99 
            d = rand() % c ; //保证d小于d 0~c-1
            if (cur_oper == '/') 
            { 
                if (d == 0) 
                { d = d + 1;
                c = rand() % 98 + 2;
                } 
                cout << b << "/" << a << " " << cur_oper << " " << d << "/" << c << "=" << endl;
            }
            else 
                cout << b << "/" << a << " " << cur_oper << " " << d << "/" << c << "=" << endl;
            break;
        }
    }
    return 0;
}