using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        Monnaie m = MonnaieOptimale(101);

        if(m == null)

        {

            Console.WriteLine("Impossible");

        }

        else

        {

            Console.WriteLine(m.ToString());

        }

    }

    private static Dictionary<long, long> MonnaieOptimale(long s, List<long> billsFaceAmounts)

    {

        if(billsFaceAmounts.Count == 0)

        {

            return null;

        }

        Dictionary<long, long> bills = new Dictionary<long, long>();

        foreach (int billFaceAmount in billsFaceAmounts)

        {

            bills[billFaceAmount] = 0;

        }

        long rest = s;

        bool succeded = false;

​

        foreach (int billFaceAmount in billsFaceAmounts)

        {

            if(billFaceAmount > rest)

            {

                continue;

            }

            long billNumber = rest / billFaceAmount;

            bills[billFaceAmount] = billNumber;

​

            rest = rest - (billNumber * billFaceAmount);

            if(rest == 0)

            {

                succeded = true;

                break;

            }

        }

        if(!succeded)

        {

            return MonnaieOptimale(s, billsFaceAmounts.GetRange(1, billsFaceAmounts.Count - 1));

        }

        return bills;

    }

    private static Monnaie MonnaieOptimale(long s)

    {

        // it's important to keep the list sorted DESC

        List<long> billsFaceAmounts = new List<long>() {10, 5, 2};

        Dictionary<long, long> bills = MonnaieOptimale(s, billsFaceAmounts); 

        if(bills == null)

        {

            return null;

        }

        Monnaie m = new Monnaie();

        m.Billet10 = bills.ContainsKey(10) ? bills[10] : 0;

        m.Billet5 = bills.ContainsKey(5) ? bills[5] : 0;

        m.Piece2 = bills.ContainsKey(2) ? bills[2] : 0;

        return m;

    }

}

​

public class Monnaie

{

    public long Piece2

    {

        get ;

        set;

    }

    public long Billet5

    {

        get ;

        set;

    }

    public long Billet10

    {

        get ;

        set;

    }

    public override string ToString()

    {

        return Billet10 + " billet(s) de 10" + Environment.NewLine + Billet5 + " billet(s) de 5" + Environment.NewLine + Piece2 + " pieces(s) de 2";

    }

}

​