using System;

public class Program

{

    public const int LEN = 2700;

    private static int[][] _map { get; set; }

    public static void Main()

    {

        _map = new int[LEN][];

        for (int i = 0 ; i < LEN ; ++i)

        {

            _map[i] = new int[LEN];

        }

        // Run it 8 times, to give more visible results

        const int TEST_COUNT = 8;

        for (int i = 0; i < TEST_COUNT; ++i)

        {

            //Test1(); // ~3.2s

            //Test2(); // ~0.62s

            //Test3();  // ~0.23s

        }

​

    }

    public static void Test1()

    {

        long result = 0;

        for (int i = 0; i < _map.Length; i++)

        {

            for (int n = 0; n < _map.Length; n++)

            {

                if (_map[n][i] > 0)

                {

                    result++;

                }

            }

        }

    }

    public static void Test2()

    {

        long result = 0;

        for (int i = 0; i < _map.Length; i++)

        {

            for (int n = 0; n < _map.Length; n++)

            {

                if (_map[i][n] > 0)

                {

                    result++;

                }

            }

        }

    }

    public static void Test3()

    {

        long result = 0;

        int[][] map = _map;

        int len = map.Length;

        for (int i = 0; i < len;)

        {

            for (int n = 0; n < len;)

            {

                if (map[i][n] > 0)

                {

                    result++;

                }

                n++;

                if (map[i][n] > 0)

                {

                    result++;

                }

                n++;

            }

            i++;

            for (int n = 0; n < len;)

            {

                if (map[i][n] > 0)

                {

                    result++;

                }

                n++;

                if (map[i][n] > 0)

                {

                    result++;

                }

                n++;

            }

            i++;

        }

    }

​

}