Prime numbers

[gapper]

Hello Guys,

I am working on an assignment for find first 1000 prime numbers. Any help would be appreciated

I would like recursive method if possible.

Cheers.

[tim]

Hello gapper

Here's a spoiler:

Code:

public class Prime{
	protected Vector<Integer> getFactors(int integer){
		Vector<Integer> result = new Vector<Integer>();
		for (int i = 1; i <= integer; i++)
			if (integer % i == 0) result.add(new Integer(i));
		return result;
	}
	public Prime(int bound){
		System.out.println("Prime numbers up to " + bound + ":");
		for (int i = 2; i <= bound; i++){
			if (getFactors(i).size() == 2) System.out.println(i);
		}
	}
}

Use the constructor to run it

Code:

new Prime(20);

gives Output

Code:

Prime numbers up to 20:
2
3
5
7
11
13
17
19

This is a classical assignment. I could not resist.

[Cnu]

class PrimeNumbers
{
public static void main(String[] args)
{
int i,j;
i=1;
while(i<=1000)
{
j=2;
while(j<=i-1)
{
if(i%j==0) break;
j++;
}
if(i==j)
System.out.print(i);
i++;
}
}
}

[divyachaparala]

public class PrimeNumber
{

public static void main(String[] args)
{

prime pr = new prime();
int number=Integer.parseInt(args[0]);
int[] primeNum=pr.primeNumbers(number);
System.out.print("PRIME numbers are:");
for (int k = 0; k< primeNum.length; k++)
{
System.out.print(" "+primeNum[k]);
}
}
}



public class prime
{



int[] primeNumbers(int primeno)
{

int factCount=0;
int result[]=new int[4];
int k=0;

int j=0;

while(j<=primeno)
{
for(int i=2;i<=j;i++)
{
if(j%i==0)
{
factCount++;
}
}
if(factCount==1)
{
result[k]=j;

k++;
}
else
{


}
j++;
factCount=0;
}
return result;


}

}