urgent sieve of eratossthenes prime #'s

[javaman90]

alright i need some help making a program that displays all the prime number from 1-1000. i can make one but i cant make one with arrays. need help!

[horace1]

alright i need some help making a program that displays all the prime number from 1-1000. i can make one but i cant make one with arrays. need help!

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[javaman90]

this is what i have done

package prime;

public class Prime {
public static void main(String[] args) {
int i,j,p;
for(i=2;i<=1000 ;i++)
{
p = 0;
for(j=2;j<=i/2;j++)
{
if(i%j == 0)
{
p = 1;
break;
}
}
if(p == 0)
System.out.prin tln(i);
}
}

}

it works, however i need to have it as arrays, which i am unable to do...could i possibly get help on this??

[r035198x]

 

import static java.lang.Math.*;
public class testPrime{
 public static void main(String[] args) {
  int limit = 7000;
  int i,j;
  int[] intervals = new int[7];
  for(int h = 0; h < intervals.length; h++) {
   intervals[h] = 0;
  }
  boolean []prime = new boolean[limit+1];
  for(i = 2; i <= limit; i++) {
   prime[i] = true;
   int max = (int)sqrt(i) + 1;
   for(j = 2;j < max; j++){
	if((i % j) == 0) {
	 prime[i] = false;

	} 

   }
   if(prime[i] == true) {
	if(i <= 1000) {
	 intervals[0]++;
	}
	else if(1000 < i && i <= 2000) {
	 intervals[1]++;
	}
	else if(2000 < i && i <= 3000) {
	 intervals[2]++;
	}
	else if(3000 < i && i <= 4000) {
	 intervals[3]++;
	}
	else if(4000 < i && i <= 5000) {
	 intervals[4]++;
	}
	else if(5000 < i && i <= 6000) {
	 intervals[5]++;
	}
	else if(6000 < i && i <= 7000) {
	 intervals[6]++;
	}
	//System.out.println(i+\" is_prime**\");
   }
   else {
	//System.out.println(i+\" no_prime\");
   }
  }
  System.out.println(\"Highest  interval \" + testPrime.dense(intervals) + 1);

  int scale = 110;
  int n = 1000;
  for(int k = 0; k < intervals.length;k++) {

   System.out.print((n - 999) + \"-\" + n );
   if(k == 0) {
	System.out.print(\"   \");
   }
   System.out.print(\" :\");
   for(int l = 0; l < intervals[k] - scale; l++) {

	System.out.print(\"*\");
   }
   System.out.println(\"\"+intervals[k]);
   n = n + 1000;
  }

 }
 public static int dense(int[] a) {
  int highest = 0;

  for(int i = 1; i < a.length;i++) {
   if(a[i] > a[highest]) {
	highest = i;
   }
  }
  return highest;
 }
}