Spiral traversal of matrix in ruby

Ruby program for Spiral traversal of matrix. Here problem description and other solutions.

#  Ruby program for 
#  Spiral form of matrix
class SpiralView 
	def spiral(data, startRow, startCol, 
               endRow, endCol, element) 
		i = startCol
		#  Left to right
		while (i <= endCol && element > 0) 
			element -= 1
			print("  ", data[startRow][i])
			i += 1
		end

		i = startRow + 1
		#  Top to down
		while (i <= endRow && element > 0) 
			element -= 1
			print("  ", data[i][endCol])
			i += 1
		end

		i = endCol - 1
		#  Bottom right to bottom-left
		while (i >= startCol && element > 0) 
			element -= 1
			print("  ", data[endRow][i])
			i -= 1
		end

		i = endRow - 1
		#  Bottom left to top
		while (i > startRow && element > 0) 
			element -= 1
			print("  ", data[i][startRow])
			i -= 1
		end

		if (startRow + 1 <= endRow - 1 && element > 0) 
			#  Recursive call
			self.spiral(data, startRow + 1, 
                        startCol + 1, endRow - 1, 
                        endCol - 1, element)
		end

	end

end

def main() 
	task = SpiralView.new()
	#  Given matrix
	matrix = [
		[1, 2, 3, 4, 5, 6],
		[22, 23, 24, 25, 26, 7],
		[21, 36, 37, 38, 27, 8],
		[20, 35, 42, 39, 28, 9],
		[19, 34, 41, 40, 29, 10],
		[18, 33, 32, 31, 30, 11],
		[17, 16, 15, 14, 13, 12]
	]
	row = matrix.length
	col = matrix[0].length
	#  Get the number of element
	element = row * col
	task.spiral(matrix, 0, 0, row - 1, col - 1, element)
end

main()

Output

  1  2  3  4  5  6  7  8  9  10  11  12  13  14  15  16  17  18  19  20  21  22  23  24  25  26  27  28  29  30  31  32  33  34  35  36  37  38  39  40  41  42