lastMatrix

using System;

class CheckStringEqualSequence
{
    static void Main()
    {
        string[,] matrix = {
            {"ha", "ha", "hi", "hi"},
            {"fo", "ha", "ha", "xx"},
            {"xxx", "fo", "ha", "ha"},
            {"xxx", "1", "fo", "ha"},
            {"xxx", "1", "4", "fo"},

        };
        //string[,] matrix = {
        //    {"s", "qq", "s"},
        //    {"pp", "pp", "s"},
        //    {"pp", "qq", "s"},
        //};

        int countVertical = 0;
        int countHorizontal = 0;
        int countDiagonalLeftUp = 0;
        int countDiagoanlRightUp = 0;
        string strVertical = null;
        string strHorizontal = null;
        string strDiagonalLeftUp = null;
        string strDiagonalRightUp = null;

        // Horizontal - row
        for (int row = 0; row < matrix.GetLength(0); row++)
        {
            int currentCount = 0;
            for (int col = 0; col < matrix.GetLength(1) - 1; col++)
            {
                if (matrix[row, col] == matrix[row, col + 1])
                {
                    currentCount++;
                }
                else
                {
                    currentCount = 0;
                }
                if (countHorizontal < currentCount)
                {
                    countHorizontal = currentCount;
                    strHorizontal = matrix[row, col];
                }
            }
        }

        // Vertical - col
        for (int col = 0; col < matrix.GetLength(1); col++)
        {
            int currentCount = 0;
            for (int row = 0; row < matrix.GetLength(0) - 1; row++)
            {
                if (matrix[row, col] == matrix[row + 1, col])
                {
                    currentCount++;
                }
                else
                {
                    currentCount = 0;
                }
                if (countVertical < currentCount)
                {
                    countVertical = currentCount;
                    strVertical = matrix[row, col];
                }
            }
        }

        // LeftUp - Diagonal --- (last row - 1 ) to (first row)
        int myCount1 = 1;
        for (int row = matrix.GetLength(0) - 2; row >= 0; row--)
        {
            int currentCount = 0;
            for (int col = 0; col < myCount1; col++)
            {
                if (matrix[row + col, col] == matrix[row + col + 1, col + 1])
                {
                    currentCount++;
                }
                else
                {
                    currentCount = 0;
                }
                if (countDiagonalLeftUp <= currentCount)
                {
                    countDiagonalLeftUp = currentCount;
                    strDiagonalLeftUp = matrix[row + col, col];
                }
            }
            if (matrix.GetLength(0) - 1 - row < matrix.GetLength(1) - 1) // Check the count ROW or COL is bigger!!!
            {
                myCount1++;
            }
            else
            {
                myCount1 = matrix.GetLength(1) - 1;
            }
        }

        // LeftUp - Diagonal --- (first row ) to (last col)
        int myCount2 = matrix.GetLength(0) - 1;
        for (int col = 1; col < matrix.GetLength(1) - 1; col++)
        {
            int currentCount = 0;
            for (int row = 0; row < myCount2; row++)
            {
                if (matrix[row, col + row] == matrix[row + 1, col + row + 1])
                {
                    currentCount++;
                }
                else
                {
                    currentCount = 0;
                }
                if (countDiagonalLeftUp <= currentCount)
                {
                    countDiagonalLeftUp = currentCount;
                    strDiagonalLeftUp = matrix[row, col + row];
                }
            }
            if (matrix.GetLength(1) - 1 - col < matrix.GetLength(0) - 1) // Check the count ROW or COL is bigger!!!
            {
                myCount2--;
            }
            else
            {
                myCount2 = matrix.GetLength(0) - 1;
            }
        }

        // Print the result
        Console.Write("The Horizontal is: ");

        for (int i = 0; i <= countHorizontal; i++)
        {
            Console.Write(strHorizontal + " ");
        }
        Console.WriteLine();

        Console.Write("The Vertical is: ");

        for (int i = 0; i <= countVertical; i++)
        {
            Console.Write(strVertical + " ");
        }
        Console.WriteLine();

        Console.Write("The LeftUp Diagonal is: ");
        for (int i = 0; i <= countDiagonalLeftUp; i++)
        {
            Console.Write(strDiagonalLeftUp + " ");
        }
        Console.WriteLine();
    }
}