软件工程个人作业01

软件工程作业01

写一个能自动生成三十道小学四则运算题目的 “软件”，要求：除了整数以外，还要支持真分数的四则运算（需要验证结果的正确性）、题目避免重复、可定制出题的数量。

思路：

1、通过产生随机数生成百以内的int类型数据，包装方法，在方法中通过随机的方法确定这个数据是否为分数，如果为分数，则产生两个随机数相除，为保证为真分数，在生成算式之前进行判断，如果分母小于分子，则分母等于分子＋分母。

2、判断是否重复：定义一个String类型数组，将生成的算式保存，每次输出之前先验证是否存在，如果存在则不输出，不计数。

  1 package demo;
  2 
  3 import java.util.*;
  4 
  5 public class Random {
  6     @SuppressWarnings("resource")
  7     public static void main(String args[])
  8     {
  9         Scanner sc = new Scanner(System.in);
 10         int num;
 11         System.out.println("请输入需要生成的个数。");
 12         num = sc.nextInt();
 13         String[] s = new String[100];//保存已有的运算式
 14         int ss = 0;//运算式个数计数
 15         char[] ch = new char[4];
 16         ch[0] = '+';
 17         ch[1] = '-';
 18         ch[2] = '*';
 19         ch[3] = '/';
 20         int a,b,a1,b1;
 21         double A,B,A1,B1;
 22         int k;
 23         String str;
 24         int flagA = 0,flagB = 0;//判断是否用真分数。
 25         for(int i = 0;i < num;i ++)
 26         {
 27             flagA = SuiJileixing();
 28             flagB = SuiJileixing();
 29             if(flagA == 1 && flagB == 1)
 30             {
 31                 a = SuiJi1();
 32                 b = SuiJi1();
 33                 k = SuiJiyunsuanfu();
 34                 str = a + " " + ch[k] + " " + b + " = ";
 35                 if(Check(s,str,ss) != 1)
 36                 {
 37                     s[ss] = str;
 38                     System.out.print(s[ss]);
 39                     A = (double)a;
 40                     B = (double)b;
 41                     show(A,B,k);
 42                     ss ++;
 43                 }
 44             }
 45             else if(flagA == 1 && flagB == 0)
 46             {
 47                 a = SuiJi1();
 48                 b = SuiJi1();
 49                 b1 = SuiJi1() + 1;
 50                 if(b < b1)
 51                 {
 52                     b = b;
 53                 }
 54                 else 
 55                 {
 56                     b1 = b1 + b;
 57                 }
 58                 k = SuiJiyunsuanfu();
 59                 str = a + " " + ch[k] + " (" + b + "/" + b1 + ") = ";
 60                 if(Check(s,str,ss) != 1)
 61                 {
 62                     s[ss] = str;
 63                     System.out.print(s[ss]);
 64                     A = (double)a;
 65                     B = (double)b;
 66                     B1 = (double)b1;
 67                     show(A,B/B1,k);
 68                     ss ++;
 69                 }
 70             }
 71             else if(flagA == 0 && flagB == 1)
 72             {
 73                 a = SuiJi1();
 74                 a1 = SuiJi1() + 1;
 75                 b = SuiJi1();
 76                 if(a > a1)
 77                 {
 78                     a1 = a + a1;
 79                 }
 80                 k = SuiJiyunsuanfu();
 81                 str = "(" + a + "/" + a1 + ") " + ch[k] + " " + b + " = ";
 82                 if(Check(s,str,ss) != 1)
 83                 {
 84                     s[ss] = str;
 85                     System.out.print(s[ss]);
 86                     A = (double)a;
 87                     A1 = (double)a1;
 88                     B = (double)b;
 89                     show(A/A1,B,k);
 90                     ss ++;
 91                 }
 92             }
 93             else
 94             {
 95                 a = SuiJi1();
 96                 a1 = SuiJi1() + 1;
 97                 b = SuiJi1();
 98                 b1 = SuiJi1() + 1;
 99                 if(a > a1)
100                 {
101                     a1 = a + a1;
102                 }
103                 if(b > b1)
104                 {
105                     b1 = b + b1;
106                 }
107                 k = SuiJiyunsuanfu();
108                 str =  "(" + a + "/" + a1 + ") " + ch[k] + " " + b + "/" + b1 + " = ";
109                 if(Check(s,str,ss) != 1)
110                 {
111                     s[ss] = str;
112                     System.out.print(s[ss]);
113                     A = (double)a;
114                     A1 = (double)a1;
115                     B = (double)b;
116                     B1 = (double)b1;
117                     show(a/a1,b/b1,k);
118                     ss ++;
119                 }
120             }
121 
122             
123             
124         }
125         
126     }
127     
128     public static int SuiJi1()
129     {
130         int a;
131         a = (int)(Math.random()*100);
132         return a;
133     }
134     public static int SuiJiyunsuanfu()
135     {
136         int a;
137         a = (int) (Math.random()*4);
138         return a;
139     }
140     public static int Check(String s[],String str,int ss)
141     {
142         int qqq = 0;
143         for(int i = 0;i < ss;i ++)
144         {
145             if(str.equals(s[ss]))
146             {
147                 qqq = 1;
148                 break;
149             }
150         }
151         return qqq;
152     }
153     public static int SuiJileixing()
154     {
155         int flag = (int)(Math.random()*2);
156         return flag;
157     }
158     public static void show(double a,double b,int k)
159     {
160         if(k == 0)
161         {
162             System.out.println(a + b);
163         }
164         if(k == 1)
165         {
166             System.out.println(a - b);
167         }
168         if(k == 2)
169         {
170             System.out.println(a * b);
171         }
172         if(k == 3)
173         {
174             System.out.println(a / b);
175         }
176     }
177 }