using System;

public class Program

{

    public static void Main()

    {

        int [] arrays = new int[20];

        for(int i = 0; i < 20; ++i)

        {

            arrays[i] = i*5;

        }

        for(int i = 0; i<arrays.Length; ++i)

        {

            Console.WriteLine(i+ " "+arrays[i]);

        }

            }

            }