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1. [10pts] Consider the following program:

   HWEX1.java	Rat.java	Identify each of the following as either primitive, an array-reference or a class-reference: args __________________ subj1 __________________ sc __________________ nm __________________ wt __________________ wtInGrams __________________ r __________________ r.name __________________ r.weight __________________
   import java.util.*; public class HWEX1 { public static Rat read() { Scanner sc = new Scanner(System.in); String nm = sc.next(); double wt = sc.nextDouble(); double wtInGrams = wt*28.3495; Rat r = new Rat(); r.name = nm; r.weight = wtInGrams; return r; } public static void main(String[] args) { Rat subj1 = read(); } }	class Rat { String name; double weight; }

2. [5pts] Continuing from the previous example, how many instances of class Rat are created when this program is run? How many instances of class String are created when the function read() is called, assuming the user inputs name & weight properly. Explain your answers! [Note: "instance" is a technical term. Read the notes!]
3. [5pts] Consider the following file HWEX2.java:

   public class HWEX2 { public static int fact(int n) { return n < 2 ? 1 : n*fact(n-1); } public static void main(String[] args) { for(int i = 1; i < 10; i++) System.out.println(i + ": " + fact(i)); } }

   How would you call the function fact to compute 15 factorial from the main function of another .java file (assume it is HW.java)? If you run the program from HW.java (i.e. give the command java HW), how does the JVM know where to find the code for the fact function?

   
   
4. [80Pts]

   Create a file entitled Mid.java and put this class definition in it:

   public class Mid 
   {
     public String alpha;
     public String firstName;
     public String lastName;
     public int company;
   }

   Then write a program entitled HW3.java with the following attributes:

   • A createMid method that takes a Scanner as argument and asks the user for the information necessary to construct a Mid. It then returns that Mid.
   • A printMid method that takes a Mid as an argument and prints the information about that Mid to the screen in the format shown below.
     Note: When you print the alpha code, any leading zeros should print properly. For example: '012226'. That's why we are storing "alpha" as a string rather than an int (the other alternative is to take more time for formatted numerical output than I want to right now).
   • A main method that 1) reads in a number of mids, 2) reads info for that many mids, 3) reads in a company number, 4) prints the info for the mids from that company in the same order as read in. You should, of course, use "createMid" and "printMid".
   • You should have two files, 'Mid.java' and 'HW3.java'

   Example Runs
   $ java HW3 5 230531 Noah Taylor 3 233159 Sophia White 17 236234 Jackson Miller 3 237198 Isabella Wilson 17 234735 Aiden Brown 3 3 230531 Noah Taylor 3 236234 Jackson Miller 3 234735 Aiden Brown 3	$ java HW3 5 230531 Noah Taylor 3 233159 Sophia White 17 236234 Jackson Miller 3 237198 Isabella Wilson 17 234735 Aiden Brown 3 17 233159 Sophia White 17 237198 Isabella Wilson 17	$ java HW3 5 230531 Noah Taylor 3 233159 Sophia White 17 236234 Jackson Miller 3 237198 Isabella Wilson 17 234735 Aiden Brown 3 12

submit -c=IC211 -p=hw03 HW3.java Mid.java