using System;

using System.Linq;

using System.Collections.Generic;

public class Program

{

    /**

     * @param tenors La liste ne doit pas être modifié !

     */

    public static List<string> Sort(string[] tenors) {

        // Write your code here

        IList<KeyValuePair<string,int>> dictionnary = new List<KeyValuePair<string,int>>();

        foreach(var tenor in tenors)

        {

            int.TryParse(tenor.Substring(0, tenor.Length-1), out int val);

​

            switch (tenor.Last<char>())

            {

                case 'D' : 

                    dictionnary.Add(KeyValuePair.Create(tenor, int.Parse(tenor.Substring(0, tenor.Length-1))));

                    break; 

                case 'W' : 

                    dictionnary.Add(KeyValuePair.Create(tenor, int.Parse(tenor.Substring(0, tenor.Length-1))*7));

                    break; 

                case 'M' : 

                    dictionnary.Add(KeyValuePair.Create(tenor, int.Parse(tenor.Substring(0, tenor.Length-1))*30));

                    break; 

                case 'Y' : 

                    dictionnary.Add(KeyValuePair.Create(tenor, int.Parse(tenor.Substring(0, tenor.Length-1))*365));

                    break; 

                default : 

                    throw new Exception("Format not valid");

            }

        }

​

        return dictionnary.OrderBy(x => x.Value).Select(x => x.Key).ToList();

    }

    public static void Main()

    {

        string[] tenors =

        {

            "40Y",

            "2D",

            "11Y",

            "8Y",

            "12Y",

            "1M",

            "2M",

            "3M",

            "4M",

            "5M",

            "6M",

            "25Y",

            "9M",

            "12D",

            "1Y",

            "2M",

            "18M",

            "2Y",

            "3Y",

            "4Y",

            "5Y",

            "6Y",

            "1D",

            "7Y",

            "9Y",

            "10Y",

            "13Y",

            "2D",

            "1W",

            "14Y",

            "15Y",

            "20Y",

            "30Y",            

            "50Y"

        };

        var sortedTenors = Sort(tenors);

        Console.WriteLine("Initial : [{0}]", string.Join(", ", tenors));

        Console.WriteLine("Sorted  : [{0}]", string.Join(", ", sortedTenors));

    }

}