mithilesh kumar singh

A
A B
A B C
A B C D
A B C D E

class Program

    {

        static void Main(string[] args)

        {

            for (int row = 65; row < 70; row++)

            {

                for (int coll = 65; coll <= row; coll++)

                {

                    Console.Write(Convert.ToChar(coll));

                }                Console.WriteLine();

            }

            Console.ReadLine();

        }

    }