CSCI 202 Homeworks 2 & 7

Rules of submission

This assignment must be submitted either in class on Thursday, 21 March, or uploaded to the Moodle submission page for Homeworks 2 & 7 by 6:00 PM on Thursday, 21 March.

Homework 2 revisted

The Homework 2 asked you to indicate the tokens in a Java class. This didn&nbsdp;t work out well, so we re going to try it again.

Just to make it clear what is desire, the tokens on the following line of Java code
    String s = "hi " + (int) /* hi */ (2.5 * ( k +j)) ;
are the following:

• String
• s
• =
• "hi "
• +
• (
• int
• )
• (
• 2.5
• *
• (
• k
• +
• j
• )
• )
• ;

Having seen this example, redo the Homework 2 example, repeated below. I strongly suggest you circle the tokens. Outlining them just doesn t work. The individual tokens all run together.

package edu.unca.cs.csci202.jan222012;

  // A Java program of sorts

public class Example1 {

    public static void /* of use */ main(String[] args) {
        int x = (int)(3.14 / (5 << 2)) ;
        for (int i=x; i<202; ++i) {
            System.out.println("This is line " + i) ;
        }
        System.out.println("abcd" == "ab" + "cd") ;
        System.out.println("abcd".equals("ab".concat("cd"))) ;
    }
}

Homework 7

In this homework, you are to show all the subexpressions of a Java expression. You should follow the expression structure discussed in the Quick look at legal Java expressions lecture.

As an example, let’s try out the following Java expression:
    x = (int)(3.14 / (5 << 2))
Its subexpressions are shown below. In your answer, it’s not necessary to short the “sort” of the expresion.

Inspired by this example, find the subexpressions of the following. You can do this by circling the subexpressions, but you will need to used a large font (or handwriting) to make it readable.

degree = ( (int) (r * 180 / Math.PI ) + 90) % 360