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;
import java.util.Arrays;
import java.lang.*;
public class mitul
{
       public static void main(String args[])
       {
              Scanner scan = new Scanner(System.in);
              int n = scan.nextInt();
             int[] arr = new int[n];
             int F=0;
             int k=0,count=0;
             for(int i=0;i<n;i++)
             {
                    arr[i]=scan.nextInt();
             }
             for(int i=0;i<arr.length-1;i++)
             {
                    if(arr[i]!=0)
                    {
                    F=0;
                    for(int j=i+1;j<arr.length;j++)
                    {
                          if(arr[i]==arr[j])
                          {
                                 F=1;
                                 break;
                          }
                          
                    }
                    if(F==0)
                    {
                          //System.out.println(arr[i]);
                          count++;
                    }
                    }
             }
             count++;
       System.out.println(count);
       }
}