要求變量只有如果爲真

Question

我爲我的CSE 20課程做了第一個項目，我必須編寫一個簡單的租賃汽車系統。我一開始就陷入困境。我需要問車子，天數，然後你是否是俱樂部會員。如果你的代碼不需要繼續並輸出它的總數。但是如果你是一個俱樂部會員，它必須提出另一個關於高管包的問題，​​那麼這就增加了總輸出的另一條線。我不知道如何編寫代碼才能完全運行。任何幫助，將不勝感激。

import java.util.Scanner; 

public abstract class Bobcar1 { 

public static void main(String[] args) { 
    // TODO Auto-generated method stub 

    Scanner blah = new Scanner(System.in); 
    System.out.println("Available cars: 1 for Econobox, 2 for Compact, 3 for Standard"); 
    System.out.print("Please choose the rental car: "); 
    int car; 
    car = blah.nextInt(); 
    System.out.print("Please enter the number of rental days: "); 
    int day; 
    day = blah.nextInt(); 
    System.out.print("Club member?: 1 for yes, 0 for no: "); 
    int re; 
    re = blah.nextInt(); 
    if (re == 1) 
     System.out.print("Platinum Executive Package?: 1 for yes, 0 for no: "); 
    int pack; 
    pack = blah.nextInt(); 
    if (re == 0) then what do i code here to get the program to run through completely? 

    if (car == 1) { 
      int car1; 
      car1 = (25 * day); 

        System.out.println("Base: " + day + " day(s) for a Econobox @ $25 per day:  " + "+$" + car1); 
        if (pack == 0 && re == 0)  { 
        System.out.println(); 
        System.out.println("Total Estimate for Rental:     " + " $" + car1); 
        } 
        if (re == 1 && pack == 0)  { 
          int re1; 
          re1 = (day/5)*25; 
        System.out.println("Club Member Discount:     " + "-$" + re1); 
          int total1r; 
          total1r = car1 - re1; 
        System.out.println(); 
        System.out.println("Total Estimate for Rental:     " + " $" + total1r); 
        } 
        if (pack == 1 && re == 1)  { 
          int pack1; 
          pack1 = (int) (car1*.20); 
        System.out.println("Platinum Executive Package:     " + "+$" + pack1);  
          int re1; 
          re1 = (day/5)*25; 
        System.out.println("Club Member Discount:     " + "-$" + re1); 
          int total1; 
          total1 = car1 + pack1 - re1; 
          System.out.println("Total Estimate for Rental:     " + " $" + total1); 
        } 
    } 
    if (car == 2) { 
      int car1; 
      car1 = (55 * day); 

        System.out.println("Base: " + day + " day(s) for a Compact @ $55 per day: " + "+$" + car1); 
        if (pack == 0 && re == 0)  { 
        System.out.println(); 
        System.out.println("Total Estimate for Rental:     " + " $" + car1); 
        } 
        if (re == 1 && pack == 0)  { 
          int re1; 
          re1 = (day/5)*55; 
        System.out.println("Club Member Discountt:     " + "-$" + re1); 
          int total1r; 
          total1r = car1 - re1; 
        System.out.println(); 
        System.out.println("Total Estimate for Rental:     " + " $" + total1r); 
        } 
        if (pack == 1 && re == 1)  { 
          int pack1; 
          pack1 = (int) (car1* .20); 
        System.out.println("Platinum Executive Package:     " + "+$" + pack1);  
          int re1; 
          re1 = (day/5)*55; 
        System.out.println("Club Member Discount:     " + "-$" + re1); 
          int total1; 
          total1 = car1 + pack1 - re1; 
          System.out.println("Total Estimate for Rental:     " + " $" + total1); 
        } 
    } 
    if (car == 3) { 
      int car1; 
      car1 = (100 * day); 

        System.out.println("Base: " + day + " day(s) for a Standard @ $100 per day:  " + "+$" + car1); 
        if (pack == 0 && re == 0)  { 
        System.out.println(); 
        System.out.println("Total Estimate for Rental:     " + " $" + car1); 
        } 
        if (re == 1 && pack == 0)  { 
          int re1; 
          re1 = (day/5)*100; 
        System.out.println("Return Customer Discount:     " + "-$" + re1); 
          int total1r; 
          total1r = car1 - re1; 
        System.out.println(); 
        System.out.println("Total Estimate for Rental:     " + " $" + total1r); 
        } 
        if (pack == 1 && re == 1)  { 
          int pack1; 
          pack1 = (int) (car1*.20); 
        System.out.println("Platinum Executive Package:     " + "+$" + pack1);  
          int re1; 
          re1 = (day/5)*100; 
        System.out.println("Club Member Discount:     " + "-$" + re1); 
          int total1; 
          total1 = car1 + pack1 - re1; 
          System.out.println("Total Estimate for Rental:     " + " $" + total1); 
    } 

}}}} 

Answer 1

您應該修改您的OP（原始帖子）以包括您在評論中發佈的問題。

如果您只想修改代碼，只詢問他們是否需要鉑金套餐，如果他們指定他們是俱樂部會員，那麼您需要修改您的代碼，以便只讀取掃描儀的輸入對於這個問題，如果你打印的問題。

換句話說，放在if語句塊的周圍。這是最佳做法，即使對於1行語句塊也是如此。

您目前有：

... 
int re; 
re = blah.nextInt(); 
if (re == 1) 
    System.out.print("Platinum Executive Package?: 1 for yes, 0 for no: "); 
int pack; 
pack = blah.nextInt(); 
... 

你可以修改你的代碼是這樣的：

... 
int pack; 
int re = blah.nextInt(); 
if (re == 1) { 
    System.out.print("Platinum Executive Package?: 1 for yes, 0 for no: "); 
    pack = blah.nextInt(); 
} 
...