static void Main()
{
byte n = byte.Parse(Console.ReadLine());
char symbol1 = '.';
char symbol2 = '*';
int leftBorderPosition = 0;
for (int row = 0; row < n + 1; row++)
{
leftBorderPosition = n - row; // Positioning the left border of the trepezoid
for (int position = 0; position < 2 * n; position++)
{
if (row == 0 && position < n) // First row first half
{
Console.Write(symbol1);
}
else if (row == 0 && position >= n) // First row second half
{
Console.Write(symbol2);
}
else if (row == n) // Last row
{
Console.Write(symbol2);
}
else if (position == leftBorderPosition || position == 2 * n - 1) // Left and right borders
{
Console.Write(symbol2);
}
else
{
Console.Write(symbol1); // Inside and outside the trapezoid
}
}
Console.WriteLine();
}
}
}
