zoukankan      html  css  js  c++  java
  • 第一次作业--四则运算

    功能:

        1.将用户的输入作为参数n

        2.算式的运算符数量不超过3个(随机生成1-3运算符的算式)

        3.组成算数表达式

        4.判断用户的答案是否正确

        5.计算题目结果并输出文档

        6.比较答案并给出错误题号

    设计分析:

        1.表达式不重复

        2.考虑分数的情况

    程序设计

    • 功能点1:生成随机数

      随机数生成方法:
          public Num createNum(int range)
     1 package method;
     2 
     3 import java.util.Random;
     4 import method.Num;
     5 
     6 public class randomNum {
     7     public Num createNum(int range) {
     8         Num num = new Num();
     9         Random rand = new Random();
    10         int numerator = rand.nextInt(range + 1);
    11         int denominator = rand.nextInt(10) + 1;
    12         if (rand.nextInt(1) == 1) {
    13             num.setNumerator(numerator);
    14             num.setDenominator(1);
    15         } else {
    16             num.setNumerator(numerator);
    17             num.setDenominator(denominator);
    18         }
    19         num = reduction(num);
    20         return num;
    21     }
    22 
    23     public Num reduction(Num num) {
    24         int numerator = num.getNumerator();
    25         int denominator = num.getDenominator();
    26         if (numerator == 0) {
    27             num.setDenominator(1);
    28             return num;
    29         }
    30         int divisor = getMaxDivisor(numerator, denominator);
    31         if (divisor == 1) {
    32             return num;
    33         } else {
    34             num.setNumerator(num.getNumerator() / divisor);
    35             num.setDenominator(num.getDenominator() / divisor);
    36             return num;
    37         }
    38     }
    39 
    40     public int getMaxDivisor(int numerator, int denominator) {
    41         if (denominator == 0) {
    42             return numerator;
    43         } else {
    44             return getMaxDivisor(denominator, numerator % denominator);
    45         }
    46     }
    47 }
    • 功能点2:生成随机运算符

      随机运算符生成方法:
          public String createOperator()
     1 package method;
     2 
     3 import java.util.Random;
     4 
     5 public class randomOperator {
     6     public String createoperator() {
     7         String operator = null;
     8         Random rand = new Random();
     9         int n = rand.nextInt(4);
    10         switch (n) {
    11         case 0:
    12             operator = "+";
    13             break;
    14         case 1:
    15             operator = "-";
    16             break;
    17         case 2:
    18             operator = "*";
    19             break;
    20         case 3:
    21             operator = "÷";
    22             break;
    23         default:
    24             operator = "+";
    25             break;
    26         }
    27         return operator;
    28     }
    29 }
    • 功能点3:组成算数表达式

      表达式表示:
          类型:ArrayList
      组成方法:
          public ArrayList<Object> createArithmetic(int range)
    • 功能点4:计算表达式结果并输出文档

      逆波兰式转换:
          public ArrayList<Object> toRPN(ArrayList<Object> list)
      逆波兰式计算
          public Num countRPN(ArrayList<Object> right)
          private Num twoResult(String is, Num op1, Num op2)
      1 package method;
      2 
      3 import java.util.ArrayList;
      4 import java.util.Iterator;
      5 import method.Num;
      6 import method.Stacks;
      7 
      8 public class RPN {
      9     public ArrayList<Object> toRPN(ArrayList<Object> list) {
     10         ArrayList<Object> right = new ArrayList<Object>();// 存储右序表达式
     11         Stacks aStack = new Stacks();// 栈
     12         String operator;
     13         int position = 0;// 当前指针位置
     14         while (true) {
     15             // 当前指针为符号
     16             if (isOperator(list.get(position).toString())) {
     17                 // 栈为空,或指针为(,直接进栈
     18                 if (aStack.top == -1
     19                         || ((String) list.get(position)).equals("(")) {
     20                     aStack.push(list.get(position));
     21                 } else {
     22                     // 指针为)
     23                     if (((String) list.get(position)).equals(")")) {
     24                         // 将栈内(后的运算符出栈
     25                         while (true) {
     26                             if (aStack.top != -1
     27                                     && !((String) aStack.top()).equals("(")) {
     28                                 operator = (String) aStack.pop();
     29                                 right.add(operator);
     30                             } else {
     31                                 if (aStack.top != -1)
     32                                     aStack.pop();
     33                                 break;
     34                             }
     35                         }
     36                     } else {
     37                         while (true) {
     38                             // 栈不为空,判断优先级
     39                             if (aStack.top != -1
     40                                     && priority((String) list.get(position),
     41                                             (String) aStack.top())) {
     42                                 operator = (String) aStack.pop();
     43                                 if (!operator.equals("("))
     44                                     right.add(operator);
     45                             } else {
     46                                 break;
     47                             }
     48 
     49                         }
     50                         aStack.push(list.get(position));
     51                     }
     52                 }
     53             }
     54             // 数字入栈
     55             else {
     56                 right.add(list.get(position));
     57             }
     58             position++;
     59             if (position >= list.size())
     60                 break;
     61         }
     62         // 栈内剩余运算符出栈
     63         while (aStack.top != -1) {
     64             operator = (String) aStack.pop();
     65             if (!operator.equals("("))
     66                 right.add(operator);
     67         }
     68         return right;
     69     }
     70 
     71     // 判断是否为运算符
     72     public static boolean isOperator(String operator) {
     73         if (operator.equals("+") || operator.equals("-")
     74                 || operator.equals("*") || operator.equals("÷")
     75                 || operator.equals("(") || operator.equals(")"))
     76             return true;
     77         else
     78             return false;
     79     }
     80 
     81     // 设置操作符号的优先级别
     82     public static boolean priority(String operatorout, String operatorin) {
     83         int m = 0, n = 0;
     84         String addop[][] = { { "+", "-", "*", "÷", "(", ")" },
     85                 { "+", "-", "*", "÷", "(", ")" } };
     86         int first[][] = { { 1, 1, 2, 2, 2, 0 }, { 1, 1, 2, 2, 2, 0 },
     87                 { 1, 1, 1, 1, 2, 0 }, { 1, 1, 1, 1, 2, 0 },
     88                 { 2, 2, 2, 2, 2, 0 }, { 2, 2, 2, 2, 2, 2 } };
     89         for (int i = 0; i < 6; i++) {
     90             if (operatorin.equalsIgnoreCase(addop[0][i]))
     91                 m = i;
     92         }
     93         for (int i = 0; i < 6; i++) {
     94             if (operatorout.equalsIgnoreCase(addop[1][i]))
     95                 n = i;
     96         }
     97         if (first[m][n] == 1) {
     98             return true;
     99         } else
    100             return false;
    101     }
    102 
    103     // 逆波兰式计算
    104     public Num countRPN(ArrayList<Object> right) {
    105         // 栈
    106         Stacks aStack = new Stacks();
    107         Num op1, op2, result = null;
    108         String is = null;
    109         Iterator<Object> it = right.iterator();
    110 
    111         while (it.hasNext()) {
    112             Object ob = it.next();
    113             is = ob.toString();
    114             if (isOperator(is)) {
    115                 op2 = (Num) aStack.pop();
    116                 op1 = (Num) aStack.pop();
    117                 Num do_0 = twoResult(is, op1, op2);
    118                 if (do_0.getDenominator() == 0) {
    119                     return (new Num(-1, 1));
    120                 }
    121                 aStack.push(do_0);
    122             } else
    123                 aStack.push(ob);
    124         }
    125         result = (Num) aStack.pop();
    126         return result;
    127     }
    128 
    129     // 计算两个数
    130     private Num twoResult(String is, Num op1, Num op2) {
    131         // 结果数
    132         Num result = new Num();
    133         randomNum f1 = new randomNum();
    134         // 获取分子分母
    135         int n1 = op1.getNumerator();
    136         int d1 = op1.getDenominator();
    137         int n2 = op2.getNumerator();
    138         int d2 = op2.getDenominator();
    139         // 判断运算符
    140         switch (is) {
    141         case "+":
    142             if (d1 != d2) {
    143                 n1 = n1 * d2;
    144                 n2 = n2 * d1;
    145                 d1 = d1 * d2;
    146                 d2 = d1;
    147                 result.setNumerator(n1 + n2);
    148                 result.setDenominator(d1);
    149                 result = f1.reduction(result);
    150             } else {
    151                 result.setNumerator(n1 + n2);
    152                 result.setDenominator(d1);
    153                 result = f1.reduction(result);
    154             }
    155             break;
    156         case "-":
    157             if (d1 != d2) {
    158                 n1 = n1 * d2;
    159                 n2 = n2 * d1;
    160                 d1 = d1 * d2;
    161                 d2 = d1;
    162                 result.setNumerator(n1 - n2);
    163                 result.setDenominator(d1);
    164                 result = f1.reduction(result);
    165             } else {
    166                 result.setNumerator(n1 - n2);
    167                 result.setDenominator(d1);
    168                 result = f1.reduction(result);
    169             }
    170             break;
    171         case "*":
    172             result.setNumerator(n1 * n2);
    173             result.setDenominator(d1 * d2);
    174             result = f1.reduction(result);
    175             break;
    176         case "÷":
    177             if (n2 == 0) {
    178                 result = new Num(0, 0);
    179                 break;
    180             }
    181             result.setNumerator(n1 * d2);
    182             result.setDenominator(d1 * n2);
    183             result = f1.reduction(result);
    184             break;
    185         default:
    186             break;
    187         }
    188         return result;
    189     }
    190 }
    • 功能点5:比较答案
     1 package method;
     2 
     3 import java.util.ArrayList;
     4 import java.util.Scanner;
     5 
     6 import method.Arithmetic;
     7 import method.RPN;
     8 
     9 public class Main {
    10     public static void main(String[] args){
    11         Arithmetic arithmetic = new Arithmetic();
    12         ArrayList<Object> list = arithmetic.createarithmetic(3);
    13         for (int i = 0; i < list.size(); i++) {  
    14             System.out.print(list.get(i));  
    15         }
    16         RPN rpn = new RPN();
    17         ArrayList<Object> right = rpn.toRPN(list);
    18         Num num = new Num();
    19         num = rpn.countRPN(right);
    20         String a = num.toString();
    21         Scanner answer = new Scanner(System.in);  
    22         System.out.println(); 
    23         System.out.print("输入答案:");   
    24         String name = answer.nextLine(); 
    25         if(name.equals(a)){
    26             System.out.println("正确 ");
    27         }else{
    28             System.out.println("错误 ");
    29             System.out.print("正确答案:" + a);
    30         }
    31     }
    32 }

    PSP记录表

    PSP2.1 Personal Software Process Stages Time Senior Student Time
    Planning 计划 10 10
    · Estimate 估计这个任务需要多少时间 10 8
    Development 开发 158 324
    · Analysis 需求分析 (包括学习新技术) 13 15
    · Design Spec 生成设计文档 17 8
    · Design Review 设计复审 5 3
    · Coding Standard 代码规范 10 25
    · Design 具体设计 20 50
    · Coding 具体编码 60 150
    · Code Review 代码复审 10 30
    · Test 测试(自我测试,修改代码,提交修改) 20 20
    Reporting 报告 10 50
    · 测试报告 10 20
    · 计算工作量 10 25
    · 并提出过程改进计划 20 40
     
  • 相关阅读:
    Rabbitmq的使用四_Java Client方式使用Topic模式
    CentOS7安装Redis
    nmon文件结果分析
    nmon安装
    jmeter+ant+jenkins
    jenkins插件下载加速
    jmeter:多机联合负载
    jmeter Linux负载机出错Server failed to start:
    jenkins安装
    fiddler:筛选请求响应
  • 原文地址:https://www.cnblogs.com/miracleStone/p/7586806.html
Copyright © 2011-2022 走看看