The recent All-Berland Olympiad in Informatics featured n participants with each scoring a certain amount of points.

As the head of the programming committee, you are to determine the set of participants to be awarded with diplomas with respect to the following criteria: 

  * At least one participant should get a diploma. 
  * None of those with score equal to zero should get awarded. 
  * When someone is awarded, all participants with score not less than his score should also be awarded. 



Determine the number of ways to choose a subset of participants that will receive the diplomas.

Input

The first line contains a single integer n (1 ≤ n ≤ 100) — the number of participants.

The next line contains a sequence of n integers a1, a2, ..., an (0 ≤ ai ≤ 600) — participants' scores.

It's guaranteed that at least one participant has non-zero score.

Output

Print a single integer — the desired number of ways.

Examples

Input

4
1 3 3 2


Output

3


Input

3
1 1 1


Output

1


Input

4
42 0 0 42


Output

1

Note

There are three ways to choose a subset in sample case one.

  1. Only participants with 3 points will get diplomas. 
  2. Participants with 2 or 3 points will get diplomas. 
  3. Everyone will get a diploma! 



The only option in sample case two is to award everyone.

Note that in sample case three participants with zero scores cannot get anything.
import java.util.Scanner;

public class a
{
  public static void main(String[] args)
  {
    Scanner in = new Scanner(System.in);
    int n = in.nextInt();
    int i,j,dip=0;
    int[] a = new int[n];

    for(i = 0;i < n; i++)
      a[i] = in.nextInt();

      for(i = 0 ; i < n; i++)
      {
        for(j = 0;j < n;j++)
          if(a[j] == a[i] && (j != i))
          {
            a[j] = 0;
          }

      }
    /*  for(i = 0;i < n;i++)
      {
        System.out.println(a[i]);
      }*/

    for(i = 0;i < n;i++)
    {
      if(a[i] > 0)
      {
        for(j = 0;j < n;j++)
        {

          if(a[j] >= a[i])
          {
            //if((a[j] ==  a[i]) && (j != i))
              //a[i] = 0;


            dip++;
            break;
          }
        }
      }
         }

    System.out.println(dip);






  }
}
