Assignment 1: First Programs!

Due Thursday, September 15th, before midnight

The goals of this assignment are:

  • Work with string input and output

  • Work with variables, expressions and operations

  • Get comfortable with int, double, and String

1. Task Tracker

Write a program, Tasks.java that computes the time when the user will finish their tasks. You can assume that all times are integers that represent the time on a [24-hr "military" clock. For example, 7 PM is 19:00, or 19, in this representation.

$ javac Tasks.java
$ java Tasks
Enter the current hour: 23
Enter the task duration: 5

You will finish at 4:00 o'clock.

$ java Tasks
Enter the current hour: 9
Enter the task duration: 5

You will finish at 14:00 o'clock.

Hints:

  • Use modulo % to compute the completion time.

2. Calorie Tracker

Write a program called Calories.java that computes the amount of calories a person burns in a week while walking. On average, a person burns 100 calories for each mile walked. Unlike the previous question, where we read data from the console, use command-line arguments to get the number of miles walked.

$ javac Calories.java
$ java Calories 3.5
You burned 350.0 calories!
$ java Calories 0
You burned 0.0 calories!

Hints and requirements

  • Use a double to store the number of miles

  • Use System.out.printf to print the number of calories

  • Assume that your first command line argument (e.g. args[0]) is a positive double!

It’s ok if your program throws an exception if no argument is given! When this happens, you will get a runtime error. For example 
$ java Calories
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: Index 0 out of bounds for length 0
        at Calories.main(Calories.java:3)

3. Pet Agency

You are in charge of writing a script for the Bryn Mawr Pet Adoption Agency. In Adopt.java, write a program that will ask the user for an animal, an integer, a noun, and and a decimal number. Your program should then use this information to generate a short description of what the pets need at the adoption agency. (i.e. a This question is an example of a [madlib](https://en.wikipedia.org/wiki/Mad_Libs)).

Here are two examples (user input in bold):

$ java Adopt.java
Animal: owls
Integer: 3
Noun: hats
Decimal: 1.3

Welcome to the Bryn Mawr Pet Adoption Agency!
We have 3 owls in need of hats and 1.3% of your love!

$ java Adopt.java
Animal: slugs
Integer: 3000
Noun: peaches
Decimal: 110.3

Welcome to the Bryn Mawr Pet Adoption Agency!
We have 3000 slugs in need of peaches and 110.3% of your love!

Hints:

  • Use either a float or double variable to hold the decimal type

  • Use System.out.printf to print the decimal value with single precision.

4. What to hand-in

  1. The programs, Task.java, Calories.java, and Adopt.java.

  2. Make sure each program has a header containing your name, date, and purpose of the program

  3. A brief write-up containing your name, assignment number, and a few sentences about how long you spent on the assignment, any customizations you made, and any interesting bugs you solved.

4.1. How to hand-in

  1. Copy your programs to your dropbox, into the folder called A01.