自动生成四则运算题目

设计思想：

算术表达式为      e := n | e₁ + e₂ | e₁ − e₂ | e₁ × e₂ | e₁ ÷ e₂ | (e) , 其中e, e₁和e₂为表达式，n为自然数或真分数

#include "stdafx.h"
#include <iostream>
using namespace std;
int main()
{
    int a, b, c, d, e; //定义几个整形变量
    for (int i = 0;i<30;i++)
    {
        a = 1 + rand() % 100; //产生随机数
        b = 1 + rand() % 100;
        c = 1 + rand() % 100;
        d = 1 + rand() % 4;
        e = rand() % 2;

        if (e == 0) //当e=0的时候，进行的是整数四则运算
        {
            switch (d)
            {
            case 1:
                cout << a << "+" << b << "=" << endl;
                break;
            case 2:
                cout << a << "-" << b << "=" << endl;
                break;
            case 3:
                cout << a << "*" << b << "=" << endl;
                break;
            case 4:
                cout << a << "/" << b << "=" << endl;
                break;
            }
        }
        else(e == 1); //当e=1的时候，进行的是真分数参与的四则运算
        {
            if (c>a)

                switch (d)
                {
                case 1:
                    cout << "(" << a << "/" << c << ")" << "+" << b << "=" << endl;
                    break;
                case 2:
                    cout << "(" << a << "/" << c << ")" << "-" << b << "=" << endl;
                    break;
                case 3:
                    cout << "(" << a << "/" << c << ")" << "*" << b << "=" << endl;
                    break;
                case 4:
                    cout << "(" << a << "/" << c << ")" << "/" << b << "=" << endl;
                    break;
                }
        }
    }
    return 0;
}

运行截图

 

本次作业由于以前C语言不熟悉，像同学寻求了一些帮助，从课本上找到一些例子借鉴。