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

namespace YukiCoder
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.ReadLine();
            var va = Console.ReadLine().Split().Select(int.Parse);
            int nn = va.GroupBy(n => n).Where(g => g.Count() == 1).Count();
            Console.WriteLine(nn);
            //Console.ReadLine();
        }
    }
}