Homework 4

1. Prime Number Seive - the purpose is to determing all of the numbers between 1 and 100 that are prime.
  1. This program should create an array of size 100 (representing the numbers from 0-99). It should be an array of bools, each space indicating whether its index (the number of the space) is prime or non-prime. Start by assuming all numbers are prime.
  2. To check if is number is not prime, you check to see if it is divisible by anything larger than 1 and smaller than itself.
  3. Write a loop that starts at 2 and goes up to 10 call the number your loop increments the index. we will check each number in our array to see if it is divisible by this index. when the loop is finished, we will have done all the necessary work to determine which numbers are prime and which are not. (note: 10 is the square root of 100. if we cant to find all of the primes from 0-100, why do we stop dividing at 10? you must answer this question in the comments for your code).
  4. If a number is divisible by our index and is not equal to our index, we know it is not prime. Mark the corresponding space in the array false.
  5. After the loop is done, go through the array in another loop. If the space we are looking at is marked true, print out the index number (the number of the space we are in, ie, the 5th space). This will print out a list of every prime number from 1 to 100.

2. The Grasshopper class - slightly less offensive than cockroaches.

  1. Create a class called Grasshopper. it shold contain some variables like hunger (how hungry our grasshopper is on a scale from 1 to 10), reproduction (a boolean indicating whether or not our grasshopper has mated), and health (also a 1 to 10 scale). The class should also have several member methods. These should include hop() which makes the grasshopper hop, and probably makes it hungrier (do whatever you like, but be sure to do something), eat(), and mate() which do the corresponding things.
  2. Make all of your member variables private and write accessor functions to return their values.
  3. Write constuctor functions which let you set initial variables, as well as a default constructor.
  4. Write a class Main, which contains a main method. In that method, create in instance of a grasshopper named whatever you like ( be creative). Print out the initial values of his/her variables, make it do something, and print out the new values.