using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace yukicoderTest
{
    class Program
    {
        static void Main(string[] args)
        {
            string input = Console.ReadLine();
            string findlist = Console.ReadLine();
            string[] list = findlist.Split(' ');
            int[] num = new int[list.Length];
            int[] cnt = new int[list.Length];
            int Newcnt = 0;
            for(int i=1;i<=num.Length;i++)
            {
                cnt[i - 1] = 0;
                num[i-1] = i;
            }
            for(int i=1;i<=list.Length;i++)
            {
                for(int j=1;j<=num.Length;j++)
                {
                    if (list[i-1] == num[j-1].ToString())
                    {
                        cnt[j-1]++;
                        break;
                    }
                }
            }
            for(int i=0;i<cnt.Length;i++)
            {
                if(cnt[i]==1)
                {
                    Newcnt++;
                }

            }
            Console.WriteLine(Newcnt);
        }

    }
}