using System;

using System.Collections.Generic;

using System.Linq;

using System.Net;

using System.IO;

public class Program

{

    // Line used to parse the input

    public static string line;

    public static void Main()

    {

        // Initialize everything to parse text from a remote file

        WebClient client = new WebClient();

        Stream stream = client.OpenRead("https://pastebin.com/raw/Q85brjEq");

        StreamReader reader = new StreamReader(stream);

        // Initialize an empty List of chars to store

        // the contents of the input

        List<int> parsed_ints = new List<int>();

        // Iterate through each line of the parsed file

        while ((line = reader.ReadLine()) != null)

        {

            int i = 0;

            int.TryParse(line, out i);

            parsed_ints.Add(i);

        }

        int times = -1;

        int last_sum = 0;

        for (int i = 2; i < parsed_ints.Count; i++)

        {

            int a = parsed_ints[i-2];

            int b = parsed_ints[i-1];

            int c = parsed_ints[i];

            int sum = a+b+c;

            if (sum > last_sum) times++;

            last_sum = sum;

        }

        Console.WriteLine(times);

    }

}