using System;

public class HollowRightTriangleStarPattern

{

    public static void Main()

    {

        Console.WriteLine("Enter number of rows :");

        int rows = Convert.ToInt32(Console.ReadLine());

        for (int i = 1; i <= rows; i++)

        {

            for (int j = 1; j <= i; j++)

            {

                if (j == 1 || i == j || i == rows)

                    Console.Write("*");

                else

                    Console.Write(" ");

            }

            Console.WriteLine();

        }

        Console.ReadLine();

    }

}