Sieve

Sieve.java

import java.util.LinkedList;
import java.util.Queue;

//Sam Dodrill
//assgn page: http://penguin.ewu.edu/cscd300/Winter_12/Assignments/prog4.html

public class Sieve {
	private Queue<Integer> primes = new LinkedList<Integer>();
	private int lastMax = 0;
	private int lastCount = 0;

	public void computeTo(int max) {
		//Need to nuke these two lists
		lastMax = max;
		
		if(max < 3 && max > 0) {
			primes = new LinkedList<Integer>();
			primes.offer(1);
			
			if(max == 2) {
				primes.offer(2);
			}
		} else {
			primes = sieve(max);
		}
		
		lastCount = primes.size();
	}
	
	public static LinkedList<Integer> sieve(int n){
        Queue<Integer> primes = new LinkedList<Integer>();
        Queue<Integer> nums = new LinkedList<Integer>();

        for(int i = 2;i <= n;i++){ 
                nums.add(i);
        }
        
        //I hate do...while loops, so I converted it to a standard while loop.

        while(nums.size() > 0){
                int nextPrime = nums.remove();
                for(int i = nextPrime * nextPrime;i <= n;i += nextPrime){
                        ((LinkedList<Integer>) nums).removeFirstOccurrence(i);
                        //I know we are supposed to be using Queues here, but
                        //the convenience of this function is worth it.
                }
                
                primes.offer(nextPrime);
        }
        
        return (LinkedList<Integer>) primes;
	}

	public void reportResults() {
		int inLines = 0;
		
		for (int i : primes) {
			System.out.printf("%d\t", i);
			inLines++;
			
			if(inLines == 8) {
				inLines = 0;
				System.out.println();
			}
		}
		
		System.out.println();
	}

	public int getCount() {
		return lastCount;
	}

	public int getMax() {
		// TODO Auto-generated method stub
		return lastMax;
	}

}