/// <summary>
        /// Returns a list of coordinates that contain the character letter
        /// </summary>
        /// <param name="letter">The character that we are searching the board for</param>
        /// <returns>Returns a list of coordinates that contain the character letter</returns>
        private List<Coordinate> GetCoordinatesContainingChar(char letter)
        {
            List<Coordinate> output = new List<Coordinate>();

            for (int y = 0; y < _board.GetLength(); y++)
            {
                for (int x = 0; x < _board.GetLength(); x++)
                {
                    if (_board.GetCharAt(x, y) == letter)
                    {
                        output.Add(new Coordinate(x,y));
                    }
                }
            }

            return output;
        }
        public void TestWith1CharBoard()
        {
            List <string> lines = new List <string>();

            lines.Add("A");

            _board = new WordSearchBoard(lines);

            Assert.AreEqual(1, _board.GetLength());
        }
        public void TestWithSmallBoard()
        {
            List <string> lines = new List <string>();

            lines.Add("A,B,C");
            lines.Add("D,E,F");
            lines.Add("G,H,I");

            _board = new WordSearchBoard(lines);

            Assert.AreEqual(3, _board.GetLength());
        }