Smart_Lily

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

namespace Smart_Lily
{
    class Program
    {
        static void Main(string[] args)
        {
            int age = int.Parse(Console.ReadLine());
            double priceOfWashingMachine = double.Parse(Console.ReadLine());
            double priceOfToys = double.Parse(Console.ReadLine());
            int moneyStart = 10;
            int moneySaved = 0;
            int toys = 0;
            int brother = 0;
            double allMoney = 0.0d;
            for(int i = 1; i <= age; i++)
            {
                if(i%2==0&&i!=1)
                {
                    moneySaved = moneySaved + moneyStart;
                    moneyStart += 10;
                    brother++;
                }
                else if(i%2!=0||i==1)
                {
                    toys++;
                }
            }
            allMoney = toys * priceOfToys + moneySaved-brother;
            if(allMoney>=priceOfWashingMachine)
            {
                allMoney = allMoney - priceOfWashingMachine;
                Console.WriteLine($"Yes! {allMoney:f2}");
            }
            else
            {
                allMoney = Math.Abs(allMoney - priceOfWashingMachine);
                Console.WriteLine($"No! {allMoney:f2}");
            }
        }
    }
}