2013 Blue Bridge Cup preliminary lucky number

Problem description
The lucky number is named by the Polish mathematician Ulam. It is generated using a "sieve method" similar to the number of primes generated
。
First write the natural number 1,2,3,4,5,6,.... starting from 1
1 is the first lucky number.
We start with the number 2. Delete all items that are divisible by 2 to:
1_3_5_7_9....
Tighten them up and re-order them:
1 3 5 7 9 ..... At this point, the 3 is the 2nd lucky number, and then the number of all can be divisible by 3 ordinal position to delete. Note that is the ordinal position, not the number itself can be divisible by 3!! The deletion should be 5, 11, 17, ...
At this point 7 is the 3rd lucky number, and then delete the ordinal position can be divisible by 7 (19,39,...)
The last remaining sequence is similar to the following:
1, 3, 7, 9, 13, 15, 21, 25, 31, 33, 37, 43, 49, 51, 63, 67, 69, 73, 75, 79, ...

Input format
Enter two positive integers m n, separated by spaces (M < n < 1000*1000)
Output format
The number of lucky numbers (without M and N) that the program output is between M and N.

Sample Input 1
1 20
Sample Output 1
5

Sample Input 2
30 69
Sample Output 2

8

Import java.util.ArrayList;
Import Java.util.Scanner;
public class Xingyunshu {public

	static void Main (string[] args) {
		Scanner Scanner = new Scanner (system.in);
		int m = Scanner.nextint ();
		int n = scanner.nextint ();
		int k = 1;
		int luck = 2;
		arraylist<integer> link = new arraylist<integer> ();
		for (int i = 0; i < n; i++) {
			Link.add (i + 1);
		}

		while (Luck <= link.size ()) {for

			(int j = 1; J <= Link.size (); j + +) {
				if (j% Luck = 0) {
					link.set ( j-1, 0);
				}
			}
			for (int j = 0; J < Link.size (); j + +) {
				if ((Link.get (j)) = = 0) {
					link.remove (j);
				}
			}
			Luck = Link.get (k++);
		}
		int count = 0;
		for (int i = 0; i < link.size (); i++) {

			if (link.get (i) > M &&  link.get (i) < n) {
				count++ ;
			}
		}
		System.out.println (count);
	}
}