CMSC 10200: Lab 1

Wednesday, June 22, 2005

<-- back

Things You Need To Do Once

1. Add the following two lines of code to your .bashrc file:

     JAVABIN="/opt/java2/SunJava2-1.4.2_03/bin"
     export PATH="$JAVABIN:$HOME/local/bin:$HOME/bin:$PATH:."
   

   This will ensure that you're using the correct version of Java for this course.

2. Add the following text to your .emacs file:

   (set-background-color "white")
   

3. Make five directories inside your home directory: lab1, lab2, lab3, lab4 and lab5.

This week's exercise: practice writing some simple functions (methods) in Java

In this lab you will write functions very much like the Java fragments you've seen in class.

A necessary technicality of this exercise is that you must include the word static before your function headers. Whereas the Java fragments presented in class looked like

   boolean isZero(int n) {
     return (n==0);
   }

   static boolean isZero(int n) {
     return (n==0);
   }

We will create a framework for today's exercise as a group. Within that framework, develop the following functions:

• abs, which takes an integer and produces its absolute value
• max2, which takes two integers and returns the larger
• min2 (similar to max2)
• mean2, which takes two integers and returns a double
• gcd, as given in class
• isEven, which takes an integer and returns a boolean
• isOdd (similar to isEven)
• isNonNegative, which takes an integer and returns a boolean
• digit2english, which takes an integer between 0 and 9 and returns the English word for that integer (for example 1 -> "one")

• hypotenuse, which takes two doubles and returns a double
• max3
• min3
• med3
• isPythagoreanTriple, which takes three integers and returns a boolean
• digits, which takes an integer and returns the number of digits in that integer

• hexdigit, as in class
• hexpair, as in class
• colorCode, which takes three integers and returns the HTML-style color code (as in 255,255,0 -> #FFFF00)

You will test each function as you write it, per the instructions given in lab.

When you're finished, submit the whole lab1 folder by typing

  hwsubmit cs102 lab1