Matrix of Palindromes

namespace _2.Matrix_of_Palindromes
{
    using System;
    using System.Linq;
    using System.Text;

    class Program
    {
        static void Main()
        {
            int[] limitations = Console.ReadLine().Split(' ').Select(int.Parse).ToArray();
            int rows = limitations[0];
            int cols = limitations[1];

            StringBuilder output = new StringBuilder();
            for (int row = 0; row < rows; row++)
            {
                char firstLetter = (char) ('a' + row);
                for (int col = 0; col < cols; col++)
                {
                    output.AppendFormat("{0}{1}{2} ", firstLetter, (char) (firstLetter + col), firstLetter);
                }

                output.AppendLine();
            }

            Console.WriteLine(output.ToString().Trim());
        }
    }
}