需求分析（描述自己对需求的理解，以及后续扩展的可能性）

实现一个命令行程序，要求：

• 自动生成小学四则运算题目（加，减，乘，除）
• 支持整数
• 支持多运算符（比如生成包含100个运算符的题目）
• 支持真分数
• 统计正确率

设计思路（同时输出UML类图）

首先要输入生成题目的数目m

• 计算机根据输入的数目生成m道题
• 每道题生成的数字要随机且在0~10之间，且要生成分数
• 生成的字符也要随机且字符数在1~100之间，字符不止加减乘除，还有括号，除的时候要考虑除数不能为零
  用户输入值和计算机原本结果进行对比
• 如果正确，则输出正确
• 如果错误，则输出错误，正确答案为：输出答案，还应包括真分数计算
  答题结束后，计算机自动计算答题正确率

实现过程中的关键代码解释

计算生成题目

package CaculateSystem;
import java.util.Random;public class ProduceProblem {public int ProduceProblem () {String s = "";Random shu = new Random();//每个运算式的随机数int count = 1; //记录符号；char[] operator = new char[]{'+', '-', '*', '/'};int m = 2 + (int) (Math.random() * 6); //每个运算式数目的个数for (int j = 0; j < m; j++) {int num = shu.nextInt(10);s = s +" "+ num;if (count < m) {int c = shu.nextInt(4);s = s +" "+ operator[c];count++;}}String [] str = s.split(" ");System.out.println(s + "=");Translate t = new Translate(str);return t.flag;}
}

将中缀转换为后缀

package CaculateSystem;
import java.util.Stack;public class Translate extends Judge{int flag;public Translate (String[] args) {Stack<String> z = new Stack<String>();String jieguo = "";String t = "";for (int i = 0; i < args.length; i++) {switch (args[i]) {case "(":z.push(args[i]);break;case "+":case "-":while(z.empty() != true) {t = z.pop();if (t.equals("(")) {z.push(t);break;}jieguo = jieguo + t + " ";}z.push(args[i]);break;case "*":case "/":while(z.empty() != true) {t = z.pop();if (t.equals("+") || t.equals("-") || t.equals("(")) {z.push(t);break;}jieguo = jieguo + t + " ";}z.push(args[i]);break;case ")":while (z.empty()== false) {t = z.pop();if (t.equals("(")) {break;} else {jieguo = jieguo + t + " ";}}break;case" ":break;default:jieguo = jieguo + args[i] + " ";break;}}while (z.empty() == false) {jieguo = jieguo + z.pop() + " ";}String [] str = jieguo.split(" ");Count py = new Count(str);int answer = py.answer;flag = A(answer);}public Translate() {}
}

生成分数

package CaculateSystem;import java.util.Random;public class CreatOpNum {Rational opNum = new Rational();Random random = new Random();String opnumFile = "";String opnumPri = "";int flag;CreatOpNum(int flag1) {flag = flag1;int a = random.nextInt(9)+1;opNum.setNumerator(a);if (flag1 == 1) {//是分数int b = random.nextInt(9)+1;while (b == 0) {b = random.nextInt(9)+1;}opNum.setDenominator(b);} else {//不是分数opNum.setDenominator(1);}}public void getOpNumFile() {opnumFile = opNum.getNumerator() + " / " + opNum.getDenominator();}public void getOpNumPri() {if (flag == 0) {opnumPri = opNum.getNumerator() + "";//输出整数} else if (opNum.getNumerator() > opNum.getDenominator()) {//假分数int n = opNum.getNumerator() / opNum.getDenominator();int m = opNum.getNumerator() % opNum.getDenominator();opnumPri = n + " +  " + m + " / " + opNum.getDenominator();} else {opnumPri = opNum.getNumerator() + " / " + opNum.getDenominator();}}
}

带分数的计算

package CaculateSystem;
public class Rational {//有理数int numerator = 1;//分子int denominator = 1;//分母void setNumerator(int a) {//设置分子int c = f(Math.abs(a), denominator);//计算最大公约数numerator = a / c;denominator = denominator / c;if (numerator < 0 && denominator < 0) {numerator = -numerator;denominator = -denominator;}}void setDenominator(int b) {//设置分母int c = f(numerator, Math.abs(b));//计算最大公约数numerator = numerator / c;denominator = b / c;if (numerator < 0 && denominator < 0) {numerator = -numerator;denominator = -denominator;} else if (numerator > 0 && denominator < 0) {numerator = -numerator;denominator = -denominator;}}int getNumerator() {return numerator;}int getDenominator() {return denominator;}int f(int a, int b) {//求a,b的最大公约数if (a == 0) {return 1;//c为分母不能为0}if (a < b) {//令a>bint c = a;a = b;b = c;}int r = a % b;while (r != 0) {a = b;b = r;r = a % b;}return b;}Rational add(Rational r) {//加法运算int a = r.getNumerator();//返回有理数r的分子int b = r.getDenominator();//返回有理数r的分母int newNumerator = numerator * b + denominator * a;//计算出新分子int newDenominator = denominator * b;//计算出新分母Rational result = new Rational();result.setNumerator(newNumerator);result.setDenominator(newDenominator);return result;}Rational sub(Rational r) {//减法运算int a = r.getNumerator();int b = r.getDenominator();int newNumerator = numerator * b - denominator * a;int newDenominator = denominator * b;Rational result = new Rational();result.setNumerator(newNumerator);result.setDenominator(newDenominator);return result;}Rational muti(Rational r) {//乘法运算int a = r.getNumerator();int b = r.getDenominator();int newNumerator = numerator * a;int newDenominator = denominator * b;Rational result = new Rational();result.setNumerator(newNumerator);result.setDenominator(newDenominator);return result;}Rational div(Rational r) {//除法运算int a = r.getNumerator();int b = r.getDenominator();Rational result = new Rational();if (a == 0) {System.out.println("分母/除数不能为0");result.setNumerator(0);System.exit(0);} else {int newNumerator = numerator * b;int newDenominator = denominator * a;result.setNumerator(newNumerator);result.setDenominator(newDenominator);}return result;}
}

测试方法

运行过程截图

代码托管地址

代码托管

对结对的小伙伴做出评价（重点指出需要改进的地方）

本周我的小伙伴还是一如既往的给力，大部分的任务还是在他帮助下完成的，对我不懂的地方也认真给我解答，对我的帮助很大。

总结

本周完成了括号和分数的任务，结对真的比一个人有用，而且1+1>2是真的可以实现，虽然有的任务我们还没有完成，但是我们还会继续努力的。

PSP

参考引用

http://www.cnblogs.com/math/p/se-tools-001.html
http://www.cnblogs.com/vertextao/p/6593339.html
http://www.cnblogs.com/Vivian517/p/8762830.html
https://blog.csdn.net/newgrammer/article/details/757522
https://en.wikipedia.org/wiki/Polish_notation