随机生成30道四则运算程序分析

题目要求：随机生成30到四则运算题，其中不能超过2位运算，包含真分数。

问题细化：

1、循环30次

2、四则运算方式的表示，+，-，*，/

3、真分数的产生

4、随机产生真分数之间或者整数之间以及真分数和整数之间的运算

细化分析：

1、循环30次

2、在循环中随机产生一个1-4的随机数，表示整数运算，真分数和整数之间的运算，还是真分数之间的运算

3、在确定后，在随机产生一个1-4的随机数表示使用哪种规则，+，-，*，/

4、真分数表示使用两个随机数，要求分子比分母小，然后用“分子/分母”表示

以下是我的代码：

 

  1 #include<iostream>
  2 #include"time.h"
  3 using namespace std;
  4 
  5 
  6 //运算符两边都是整数
  7 void IntegerCount(){
  8     int first, second, work;       //work表示运算规则，first表示第一个数，second表示第二个数
  9     first = rand() % 100;
 10     work = 1 + rand() % 4;
 11     if (1 == work){                                  //1表示+，2表示-，3表示*，4表示/
 12         second = rand() % 100;
 13         cout << first << " + " << second << " = " << endl;
 14     }
 15     if (2 == work){
 16         second = rand() % 100;
 17         cout << first << " - " << second << " = " << endl;
 18     }
 19     if (3 == work){
 20         second = rand() % 100;
 21         cout << first << " * " << second << " = " << endl;
 22     }
 23     if (4 == work){
 24         second = rand() % 100;
 25         while (0 == second){
 26             second = rand() % 100;
 27         }
 28         cout << first << " / " << second << " = " << endl;
 29     }
 30 }
 31 //运算符左边是整数右边是真分数
 32 void LeftIntegerAndDecimal(){
 33     int first;
 34     int secondTop, secondBase;
 35     int work;
 36     first = rand() % 100;
 37     secondTop = rand() % 100;
 38     secondBase = 1 + rand() % 100;
 39     while (secondTop > secondBase){
 40         secondTop = rand() % 100;
 41         secondBase = 1 + rand() % 100;
 42     }
 43     work = 1 + rand() % 4;
 44     if (1 == work){
 45         cout << first << " + " << secondTop << "/" << secondBase << " = " << endl;
 46     }
 47     if (2 == work){
 48         cout << first << " - " << secondTop << "/" << secondBase << " = " << endl;
 49     }
 50     if (3 == work){
 51         cout << first << " * " << secondTop << "/" << secondBase << " = " << endl;
 52     }
 53     if (4 == work){
 54         cout << first << " / " << secondTop << "/" << secondBase << " = " << endl;
 55     }
 56 }
 57 //运算符左边是真分数左边是整数
 58 void RightIntegerAndDecimal(){
 59     int second;
 60     int firstTop, firstBase;
 61     int work;
 62     second = 1 + rand() % 100;
 63     firstTop = rand() % 100;
 64     firstBase = 1 + rand() % 100;
 65     while (firstTop > firstBase){
 66         firstTop = rand() % 100;
 67         firstBase = 1 + rand() % 100;
 68     }
 69     work = 1 + rand() % 4;
 70     if (1 == work){
 71         cout << firstTop << "/" << firstBase << " + " << second << " = " << endl;
 72     }
 73     if (2 == work){
 74         cout << firstTop << "/" << firstBase << " - " << second << " = " << endl;
 75     }
 76     if (3 == work){
 77         cout << firstTop << "/" << firstBase << " * " << second << " = " << endl;
 78     }
 79     if (4 == work){
 80         cout << firstTop << "/" << firstBase << " / " << second << " = " << endl;
 81     }
 82 }
 83 //运算符两边都是真分数
 84 void DecimalCount(){
 85     int fTop, fBase;
 86     int sTop, sBase;
 87     int work;
 88     fTop = 1 + rand()%100;
 89     fBase = fTop + rand()%100;
 90     sTop = 1 + rand()%100;
 91     sBase = sTop + rand()%100;
 92     work = 1 + rand() % 4;
 93     if (1 == work){
 94         cout << fTop << "/" << fBase << " + " << sTop << "/" << sBase << " = " << endl;
 95     }
 96     if (2 == work){
 97         cout << fTop << "/" << fBase << " - " << sTop << "/" << sBase << " = " << endl;
 98     }
 99     if (3 == work){
100         cout << fTop << "/" << fBase << " * " << sTop << "/" << sBase << " = " << endl;
101     }
102     if (4 == work){
103         cout << fTop << "/" << fBase << " / " << sTop << "/" << sBase << " = " << endl;
104     }
105 }
106 int main(){
107     int choose; //表示运算的四种种方式1、整数之间2、整数和真分数其中该方式有2种3、真分数和真分数
108     srand((unsigned)time(NULL));
109 
110     int i = 0;
111     //四种情况的运算
112     while (true){
113         choose = rand() % 4;
114         if (choose == 1){
115             IntegerCount();
116             i = i + 1;
117             //循环30次
118             if (i == 30){
119                 break;
120             }
121         }
122         if (choose == 2){
123             LeftIntegerAndDecimal();
124             i = i + 1;
125             if (i == 30){
126                 break;
127             }
128         }
129         if (choose == 3){
130             RightIntegerAndDecimal();
131             i = i + 1;
132             if (i == 30){
133                 break;
134             }
135         }
136         if (choose == 4){
137             DecimalCount();
138             i = i + 1;
139             if (i == 30){
140                 break;
141             }
142         }
143     }
144     return 0;
145 }

运行结果：

感悟：

　　使用细化方法可以使问题变得简单，可以使一些原先很难的问题得已解决。