using System;
using System.Linq;

namespace No116
{
    class Program
    {
        static void Main(string[] args)
        {
            var n = int.Parse(Console.ReadLine());
            var arr = Array.ConvertAll(Console.ReadLine().Split(' '), int.Parse);

            int count = 0;
            for (var i = 0; i <= n - 3; i++)
            {
                var kadomatsu = arr.Skip(i).Take(3).Distinct().ToArray();
                if (kadomatsu.Length != 3) continue;

                var desc = kadomatsu.OrderByDescending(x => x).ToArray();
                var center = desc[1];
                if (kadomatsu[0] == desc[1] || desc[1] == kadomatsu[2]) count++;
            }
            Console.WriteLine(count);
        }
    }
}