1.个人软件过程耗时估计与统计表
PSP2.1 | Personal Software Process Stages | predicted(h) | actual(h) |
· Planning | 计划 | 1 | 1 |
· Estimate | 估计这个任务需要多少时间 | 8 | 10 |
· Development | 开发 | 7 | 7 |
· Analysis | 需求分析 (包括学习新技术) | 1 | 0.5 |
· Design Spec | 生成设计文档 | 1 | 1 |
· Design Review | 设计复审 | 1 | 2 |
· Coding Standard | 代码规范 | 1 | 1 |
· Design | 具体设计 | 1 | 2 |
· Coding | 具体编码 | 6 | 6 |
· Code Review | 代码复审 | 7 | 9 |
· Test | 测试(自我测试,修改代码,提交修改) | 1 | 0.5 |
· Reporting | 报告 | 1 | 1 |
· | 测试报告 | 0.5 | 0.5 |
· | 计算工作量 | 0.5 | 0.5 |
· | 并提出过程改进计划 | 0.5 | 0.5 |
2.构思
因为是用java写的,所以想到用已经存在的Stack类来存放操作数和操作符,定义了两个Stack,一个存放Float类型,一个存放Character类型,用户决定出题数,但是每道题的操作数是随机出的,在这里写死了生成操作符的数目1~N,后期可以修改,只不过不想生成太长的式子,操作数就是操作符数目加一,后面如果出现乘号或除号后面出现加号或者减号,则添加括号,括号也压进操作符栈。然后事先定义一个算术符优先级表,进入一个循环,每次比较栈顶和次栈顶两个操作符的优先级,有‘<’, ‘>‘, ‘=‘,然后进行压栈入栈操作,最后操作符栈只剩下一个等于号并且操作数栈只剩一个操作数,即为整个式子答案。
3.设计
3.1、算术符优先级表
1 private static char[] signArray = new char[]{‘+‘, ‘-‘, ‘ב, ‘÷‘, ‘(‘, ‘)‘, ‘=‘}; 2 private static char[][] signPriority = new char[][]{{‘>‘, ‘>‘, ‘<‘, ‘<‘, ‘<‘, ‘>‘, ‘>‘}, 3 {‘>‘, ‘>‘, ‘<‘, ‘<‘,‘<‘, ‘>‘, ‘>‘}, {‘>‘, ‘>‘, ‘>‘, ‘>‘, ‘<‘, ‘>‘, ‘>‘}, {‘>‘, ‘>‘, ‘>‘, ‘>‘, ‘<‘, ‘>‘, ‘>‘}, 4 {‘<‘, ‘<‘, ‘<‘, ‘<‘,‘<‘, ‘=‘, ‘ ‘}, {‘>‘, ‘>‘, ‘>‘, ‘>‘, ‘>‘, ‘>‘, ‘ ‘}};
3.2、计算式子答案方法
private static Float getResult(Stack<Float> operatedNumber, Stack<Character> operatedSign) { int count = 0, flag=1; Stack<Float> tempNumber = new Stack<Float>(); Stack<Character> tempSign = new Stack<Character>(); Float newData = null, numberTop = null, numberNext = null, numberNextNext = null; Character signTop = null, signNext = null; while (operatedNumber.size() != 1 && operatedSign.size() != 1) { switch (signPriority[getPosition(operatedSign.get(operatedSign.size() - 1))][getPosition(operatedSign.get(operatedSign.size() - 2))]) { case ‘>‘: numberTop = operatedNumber.pop(); numberNext = operatedNumber.pop(); signTop = operatedSign.pop(); newData = calculate(numberTop, signTop, numberNext); operatedNumber.push(newData); break; case ‘<‘: numberTop = operatedNumber.pop(); numberNext = operatedNumber.pop(); numberNextNext = operatedNumber.pop(); signTop = operatedSign.pop(); signNext = operatedSign.pop(); if (!operatedSign.isEmpty()&& (signNext == ‘(‘ || operatedSign.get(operatedSign.size()-1)==‘(‘)) { if (operatedSign.get(operatedSign.size()-1)==‘(‘) { operatedSign.pop(); operatedNumber.push(numberNextNext); flag=0; } else { operatedNumber.add(numberNextNext); operatedNumber.add(numberNext); } while(operatedSign.get(operatedSign.size()-1)!=‘)‘) { tempSign.add(operatedSign.pop()); count++; } tempSign.push(‘=‘); for (int i =0; i<count+1; i++) { tempNumber.add(operatedNumber.pop()); } tempNumber = setNumberReserve(tempNumber); tempSign = setSignReserve(tempSign); if (flag==1) { newData = calculate(numberTop, signTop, getResult(tempNumber,tempSign)); operatedNumber.push(newData); } else { newData = calculate(numberNext, signNext, getResult(tempNumber,tempSign)); operatedNumber.push(newData); operatedNumber.push(numberTop); operatedSign.push(signTop); } } else { newData = calculate(numberNext, signNext, numberNextNext); operatedSign.push(signTop); operatedNumber.push(newData); operatedNumber.push(numberTop); } break; case ‘=‘: operatedSign.pop(); operatedSign.pop(); break; default: break; } } return operatedNumber.get(0); }
4.遇到的问题
1.某些式子算出的答案会出现负数,不符合题目要求;
解决方法;1.重新生成一个不是负数的式子,方法不太好,但是比较简单。2.避免减法出现的负数,但是由于是先生成式子,在进行计算,有一些比较长的式子,如100÷50+3-2等之类的的式子,避免负数的出现比较麻烦,因为负数不是直接因为3-2生成的。
2.计算结果的答案不正确;
入栈出栈没设计好,逻辑不够清晰,经过代码调试,解决问题。
3.生成分数的控制
分数约分问题,有点麻烦,暂时没解决。
原文:https://www.cnblogs.com/-QAQ/p/9765576.html