using System;
using System.Collections.Generic;

namespace lecture
{
    class MainClass
    {
        public static void Main(string[] args)
        {
            string row = Console.ReadLine();
            int N = int.Parse(row);

            row = Console.ReadLine();
            // 空白区切りで一旦文字列の配列に区切る
            string[] tmp = row.Split();

            Dictionary<string, int> novelty = new Dictionary<string, int>();

            for (int i = 0; i < N; i++)
            {
                string number = tmp[i];
                if (novelty.ContainsKey(number))
                {
                    novelty[number]++;
                }
                else
                {
                    novelty[number] = 1;
                }
            }

            int noveltyCnt = 0;
            foreach (int cnt in novelty.Values)
            {
                if (cnt == 1)
                {
                    noveltyCnt++;
                }
            }

            Console.WriteLine(noveltyCnt);
        }
    }
}