Name __________________________ Date: 11/22/05

AP CS Java - Mr. Merlis Block 4 ACE

Day 26 – SECOND QUARTER

à Monday, 11/28, we’ll go over the Vehicle project.

à LET’S DO LABS!

TODAY’S AGENDA

- Go over questions 11-20 from Practice Exam A1.

- Continue Lab 1 – See below [should be 100% complete by class #27]

- Start Lab 2 [due at end of class #28]

LAB 1 – “20,000 Lights” (20 points)

A room has 20,000 light bulbs, each with its own pull-string. Twenty-thousand people walk into the room, one at a time. The first person pulls each string, turning all the lights on. The second person pulls every second light bulb’s string (the 2nd, 4th, etc.) The third person pulls every third string, the fourth every fourth, and so on. Eventually the twenty-thousandth person pulls the string on the twenty-thousandth light.

A) How many light bulbs are on?

B) Which light bulbs are they?

WHAT I EXPECT

- Create a new folder called “Labs”

- Create a new project called “Lab1Lights”

- Create an application program called “Lab1Lights”

- All you will need is a main method.

LAB 2 – Working with Arraylist and Random

èOverview, Fill, print and sort an ArrayList with 50 random integers in the range 100 to 1000.

WHAT I EXPECT

- YOU SHOULD ALREADY HAVE A FOLDER called “Labs” (from last class)

- Create a new project called “Lab2List”

- Create the classes ListWorks and an application program called “Lab2”

- All methods should be static.

MAIN METHOD SHOULD LOOK LIKE:

ArrayList list = ListWorks.createList(50,100,1000);

// number of numbers, low, high à uses Java.util.Random to generate numbers.

ListWorks.print (list);

// 5 per line using EasyFormat and a for loop.

ArrayList sequence = ListWorks.createListWithMath(50, 100,1000);

//number of numbers, low, high, uses Math.random to generate numbers.

ListWorks.print (sequence,10);

// Overloaded method, 10 per line using an iterator and EasyFormat.

sequence = ListWorks.sort(sequence);

// sort will sort its parameter using a selection sort and return the sorted list

ListWorks.print(sequence);

Concepts and Classes

ArrayList, Integer, EasyFormat, Iterator, compareTo, Java.util.Random, Math.random(), overloading, selection sort, cast operator