using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Nums1to20
{
    class Program
    {
        static void Main(string[] args)
        {
            for (int a=1; a <= 20; a= a + 1)
            {
                Console.WriteLine(a);
}
            Console.ReadLine();
    }
        }
            }