20172315『Java程序設計』課程 結對編程練習_四則運算第二周階段總結
阿新 • • 發佈：2018-05-09
code pub 目的 判斷 int tint 輸入 log stat
相關過程截圖
中綴轉後綴及後綴計算測試截圖
題目生成截圖
計算正確率截圖
關鍵代碼解釋
將中綴表達式轉換為後綴表達式並對後綴表達式進行計算
import java.util.Stack; import java.util.regex.Pattern; public class StringToArithmetic { public StringToArithmetic() { } // 將中綴表達式字符串計算得到結果 public static double stringToArithmetic(String string) { return suffixToArithmetic(infixToSuffix(string)); } // 將中綴表達式轉換為後綴表達式 public static String infixToSuffix(String exp) { Stack<Character> s = new Stack<Character>(); // 要輸出的後綴表達式字符串 String suffix = ""; int length = exp.length(); // 輸入的中綴表達式的長度 for (int i = 0; i < length; i++) { char temp; char ch = exp.charAt(i); switch (ch) { case ‘ ‘: break; case ‘(‘: s.push(ch); break; case ‘+‘: case ‘-‘: while (s.size() != 0) { temp = s.pop(); if (temp == ‘(‘) { s.push(‘(‘); break; } suffix += temp; } s.push(ch); break; case ‘ב: case ‘÷‘: while (s.size() != 0) { temp = s.pop(); if (temp == ‘+‘ || temp == ‘-‘ || temp == ‘(‘) { s.push(temp); break; } else { suffix += temp; } } s.push(ch); break; case ‘)‘: while (!s.isEmpty()) { temp = s.pop(); if (temp == ‘(‘) { break; } else { suffix += temp; } } break; default: suffix += ch; break; } } while (s.size() != 0) { suffix += s.pop(); } return suffix; } public static double suffixToArithmetic(String exp) { Pattern pattern = Pattern.compile("\\d+||(\\d+\\.\\d+)"); String[] strings = exp.split(""); Stack<Double> stack = new Stack<Double>(); for (int i = 0; i < strings.length; i++) { if (strings[i].equals("")) { continue; } if (pattern.matcher(strings[i]).matches()) { stack.push(Double.parseDouble(strings[i])); } else { double y = stack.pop(); double x = stack.pop(); stack.push(calculate(x, y, strings[i])); } } return stack.pop(); } private static Double calculate(double x, double y, String string) { // TODO Auto-generated method stub if (string.trim().equals("+")) { return x + y; } if (string.trim().equals("-")) { return x - y; } if (string.trim().equals("×")) { return x * y; } if (string.trim().equals("÷")) { return x / y; } return (double) 0; }
創建題目類
public class createquestions { public static String create(int level){ String add = "+", sub = "-", multi = "×", div = "÷"; String result=""; int r1=(int)(Math.random()*9+1); int r2=(int)(Math.random()*9+1); int r3=(int)(Math.random()*9+1); //三個整數 int fenzi1=(int)(Math.random()*9+1); int fenmu1=(int)(Math.random()*9+1); String fenshu1=fenzi1+"/"+fenmu1; int fenzi2=(int)(Math.random()*9+1); int fenmu2=(int)(Math.random()*9+1); String fenshu2=fenzi2+"/"+fenmu2; int fenzi3=(int)(Math.random()*9+1); int fenmu3=(int)(Math.random()*9+1); String fenshu3=fenzi3+"/"+fenmu3; //三個分數 int suiji1=(int)(Math.random()*4); //第一個運算符 int suiji11=(int)(Math.random()*3); //生成括號 int suiji2=(int)(Math.random()*4); //第二個運算符 if (level>=1) { if(suiji11==0&&level==2&&suiji1!=0&&suiji1!=1) result+="("; if (level==3) result+=fenshu1; else result+=r1; if (suiji1 == 0) result+=add; if (suiji1 == 1) result+=sub; if (suiji1==2) result+=multi; if(suiji1==3) result+=div; if(suiji11==1&&level==2&&suiji2!=0&&suiji2!=1) result+="("; if (level==3) result+=fenshu2; else result+=r2; if(suiji11==0&&level==2&&suiji1!=0&&suiji1!=1) result+=")"; } if (level>=2){ if (suiji2==0) result+=add; if (suiji2 == 1) result+=sub; if (suiji2==2) result+=multi; if(suiji2==3) result+=div; if (level==3) result+=fenshu3; else result+=r3; if(suiji11==1&&suiji2!=0&&suiji2!=1) result+=")"; } return result; }
main類
import java.util.Scanner; public class calculate { public static void main(String[] args) { System.out.println("輸入你要生成的題數"); Scanner scan = new Scanner(System.in); int tishu = scan.nextInt(); System.out.println("輸入你要生成題目的等級(輸入1或2或3)"); int dengji = scan.nextInt(); //調用一個循環 double answer; int zhengquelv = 0; double[] daan = new double[tishu]; switch (dengji) { case 1: for (int i = 0; i < tishu; i++) { String a = createquestions.create(1); String b = a + "="; System.out.print(b); answer = scan.nextDouble(); daan[i] = StringToArithmetic.stringToArithmetic(a); if (answer == daan[i]) zhengquelv++; }break; case 2: for (int i = 0; i < tishu; i++) { String a = createquestions.create(2); String b = a + "="; System.out.print(b); answer = scan.nextInt(); daan[i] = StringToArithmetic.stringToArithmetic(a); if (answer == daan[i]) zhengquelv++; }break; case 3: for (int i = 0; i < tishu; i++) { String a = createquestions.create(3); String b = a + "="; System.out.print(b); answer = scan.nextInt(); daan[i] = StringToArithmetic.stringToArithmetic(a); if (answer == daan[i]) zhengquelv++; }break; } if(dengji<1||dengji>3) System.out.println("題目等級輸入錯誤"); if (dengji >= 1&&dengji <= 3) { System.out.println("答案為"); for ( double daanwei : daan) System.out.print(daanwei + " "); System.out.println("正確率為" + zhengquelv + "/" + tishu); } } }
遇到的困難及解決方法
關於判斷題目的正確率出現了一些小問題
經過組內商討，得出了解決辦法
寫出項目中自己負責的部分
對中綴轉後綴和後綴的計算類的編寫
個人貢獻度劃分（按百分比給小組各成員劃分貢獻度，各成員貢獻之和為100%）
20172315胡智韜30%
20172312彭霖30%
20172318陸大嶽40%
對結對的小夥伴做出評價給出小夥伴博客鏈接（重點指出需要改進的地方）
彭霖
陸大嶽
給出項目的碼雲鏈接
給出小組結對編程照片
20172315『Java程序設計』課程 結對編程練習_四則運算第二周階段總結