[BOJ C#] 5585 거스름돈

using System;

namespace _5585
{
    class Program
    {
        static void Main()
        {
            int price = int.Parse(Console.ReadLine());
            int charge = 1000 - price;
            int count = 0;

            while (charge > 0)
            {
                if (charge >= 500)
                {
                    count += (charge / 500);
                    charge %= 500;
                }
                else if (charge >= 100)
                {
                    count += (charge / 100);
                    charge %= 100;
                }
                else if (charge >= 50)
                {
                    count += (charge / 50);
                    charge %= 50;
                }
                else if (charge >= 10)
                {
                    count += (charge / 10);
                    charge %= 10;
                }
                else if (charge >= 5)
                {
                    count += (charge / 5);
                    charge %= 5;
                }
                else
                {
                    count += charge;
                    charge = 0;
                }
            }
            Console.WriteLine(count);
        }
    }
}