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

namespace YukiCoder
{
    class Program
    {
        static void Main(string[] args)
        {
            var va = Enumerable.Range(0, 7).ToList();               //  va[]={0,1,2,3,4,5,6};
            int N = int.Parse(Console.ReadLine());
            Console.ReadLine().Split().Select(int.Parse).ToList().ForEach(n => va[n] += 0x100);
            Console.WriteLine(va.Max() & 0x0F);
            Console.ReadLine();
        }
    }
}