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

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            haha:
            Console.WriteLine("Give number items");
            Console.WriteLine();
            int n = int.Parse(Console.ReadLine());
            Console.WriteLine();
            if (n < 1) goto haha;
            if (n == 1)
            {
                Console.WriteLine("Give price of item number 1");
                Console.WriteLine();
                double first = double.Parse(Console.ReadLine());
                Console.WriteLine();
                Console.WriteLine("{0} ---> {1}", first, first);
            }
            else Print(n);
            Console.WriteLine();
            Console.WriteLine();
            Console.WriteLine();
            goto haha;

        }
        static void Print(int n)
        {
            if (n == 2) IfTwo();
            else IfMore(n);
        }
        static void IfTwo()
        {
            Console.WriteLine("Give price of item number 1");
            Console.WriteLine();
            double first = double.Parse(Console.ReadLine());
            Console.WriteLine();
            Console.WriteLine("{0} ---> {1}", first, first);
            Console.WriteLine();
            Console.WriteLine("Give price of item number 2");
            Console.WriteLine();
            double second = double.Parse(Console.ReadLine());
            double sum = Math.Floor(second - (second * 0.2));
            Console.WriteLine();
            Console.WriteLine("{0} - 20% ---> {1:F0}",second, sum);
            Console.WriteLine();
        }
        static void IfMore(int n)
        {
            Console.WriteLine("Give price of item number 1");
            Console.WriteLine();
            double first = double.Parse(Console.ReadLine());
            Console.WriteLine();
            Console.WriteLine("{0} ---> {1}", first, first);
            Console.WriteLine();
            Console.WriteLine("Give price of item number 2");
            Console.WriteLine();
            double second = double.Parse(Console.ReadLine());
            double sum = Math.Floor(second - (second * 0.2));
            Console.WriteLine();
            Console.WriteLine("{0} - 20% ---> {1:F0}", second, sum);
            Console.WriteLine();
            for (int i = 3; i <= n; i++)
            {
                sum = 0;
                Console.WriteLine("Give price of item number {0}",i);
                Console.WriteLine();
                double other = double.Parse(Console.ReadLine());
                sum = Math.Floor(other - (other * 0.3));
                Console.WriteLine();
                Console.WriteLine("{0} - 30% ---> {1:F0}", other, sum);
                Console.WriteLine();
            }
        }
    }
}