Printing Triangle

using System;

class Program
{
    public static void Main(string[] args)
    {
        int n2 = int.Parse(Console.ReadLine());
        Triangle(n2);
    }
    public static void PrintLine(int a,int b)
    {
        for (int i = a; i <=b ; i++)
        {
            Console.Write(i + " ");
        }
        Console.WriteLine();
    }
    public static void Triangle(int n)
    {
        for (int i = 1; i <=n; i++)
        {
            PrintLine(1, i);
        }
        for (int i = n-1; i >= 1; i--)
        {
            PrintLine(1, i);
        }
    }
}