在程序中使用数组列表需要帮助吗？

Question

看来20个团正在形成一个连续的过程。第一个有1000人，第二个有950个，第三个有900个，等到第二十个团只有50个。在每个星期里，每个团增加了100个人，而在本周结束时，最大的团是被送到前线。这持续了20周。

对于这个程序，我已经设法打印出每个团的原始人数。但是，我很难在每个团里增加100个人。增加的人必须是军队级的一种方法。我正在使用.txt文件获取团体对象。所有这些文件包含的编号为1-20的团的名字。

public class Regiment { 

    private String name;  //name of regiment 
    private int regNumber;  //regiment number 
    private int men;   // regiment men 

    /** 
    * Creates a Regiment object. 
    * 
    * @param regNumber the regiment number 
    * @param name the name of the regiment 
    * @param men the number of men in a regiment 
    */ 
    public Regiment(int regNumber, String name, int men) { 
     this.name = name; 
     this.regNumber = regNumber; 
     this.men = men; 
    } 

    /** 
    * Returns the name of the regiment. 
    * 
    * @return the regiment name 
    */ 
    public String getName() { 
     return name; 
    } 

    /** 
    * Returns the number of the regiment. 
    * 
    * @return regiment number 
    */ 
    public int getregNumber() { 

     return regNumber; 
    } 

    /** 
    * Returns the number of men in a regiment. 
    * 
    * @return men in regiment 
    */ 
    public int getMen() { 
     return men; 
    } 

    /** 
    * Computes the number of men in a regiment 
    */ 
    public int addMen2(int RegNumber) { 

     int men = 1050 - (regNumber * 50); 
     return men; 

    } 

} 

class ArmyDataList { 

    public ArrayList<Regiment> list;  // list of regiment objects 

    /** 
    * Creates an empty list 
    */ 
    public ArmyDataList() { 
     list = new ArrayList<Regiment>(); 
    } 

    /** 
    * Appends a regiment object to the list. 
    * 
    * @param current the object to be appended to the list 
    */ 
    public void AddToList(Regiment current) { 
     list.add(current); 
    } 

    /** 
    * Removes a regiment object to the list. 
    * 
    * @param current the object to be removed from the list 
    */ 
    public void RemoveFromList(Regiment current) { 
     list.remove(current); 
    } 

    /** 
    * Gets the largest regiment based on men. 
    */ 
    public Regiment getLargest() { 
     if (list.isEmpty()) { 
      return null; 
     } 
     Regiment Reg1 = list.get(0); 

     for (int i = 1; i < list.size(); i++) { 
      Regiment current = list.get(i);  // get next regiment 
      // is current regiment > largest 
      if (current.getMen() > Reg1.getMen()) { 
       Reg1 = current; 
      } 
     } 
     return Reg1; 

    } 

    /** 
    * Adds men to each regiment. 
    */ 
    public void addMen() { 

    } 

    /** 
    * Converts the list to a multi-line string, with each line containing the 
    * data for one regiment. 
    * 
    * @return the String containing all the data on the list 
    */ 
    public String toString() { 

     String out 
       = String.format("%28s%12s%n", "Regiments", " Men") 
       + String.format("%12s%n", "Number") 
       + String.format("%12s%16s%14s%n", "=======", "===============", 
         "========="); 

     for (int i = 0; i < list.size(); i++) { 

      Regiment regim = list.get(i); 
      int regNumber = regim.getregNumber(); 
      String name = regim.getName(); 
      int men = regim.addMen2(regNumber); 

      out = out + String.format("%12s", regNumber) 
        + String.format("%16s", name) 
        + String.format("%10s", men) 
        + "\n"; 
     } 
     return out + "\n"; 

    } 
} 


public class RegimentTest { 

    public static void main(String[] args) throws IOException 
    { 


    ArmyDataList army = new ArmyDataList(); 

     // create Scanner object to read each line of file until eof 
     Scanner fileScan = new Scanner(new File("regiments.txt")); 

     System.out.println("Report Summary:\n"); 

     while (fileScan.hasNext()) // while not eof... 
     { 

     // read next line 
     String line = fileScan.nextLine(); 

     // "echo print" data entered 
     System.out.println(line); 

     // 1. create a Scanner object 
     Scanner in = new Scanner(line) ; 

     // 2. extract tokens from current line 
     int regNumber = in.nextInt(); 
     String name = in.next(); 
     int men = 0 ; //men is set to 0 only because I havent add the men yet 


     // 3. create Regiment object passing the tokens to the constructor 
     Regiment adder = new Regiment(regNumber, name, men); 

     // 4. add object to list 
     army.AddToList(adder) ; 

     } 


     System.out.println(army.toString()); 

     } 

Answer 1

你可以在军团类中编写addNewMen（）方法，你可以添加100个男人作为男人是军团的财产。