using System.Collections.Generic;

using System;

​

public class Program

{

    public static void Main()

    {

        List<int> salaryClass = new List<int>(){3001, 6001, 9001, 11001, 21010};

        salaryClass.Sort();

​

        Dictionary<string, int> data = new Dictionary<string, int>{{"Danny", 1234}, {"David",6666}, {"Dee", 9999}};  //* <name, salary>

        /* result:  

            0: [Danny],     //* < 3001

            1: [],          //* >3000  & < 6001

            2: [David],     //* >6000  & < 9001

            3: [Dee],       //* >9000  & < 11001

            4: [],          //* >11000 & < 21010  

            5: []           //* >=21010

          }

        */

        var result = GroupByRank(salaryClass, data);

        ShowDic(result);

    }

    public static Dictionary<int, List<string>> GroupByRank(List<int> list, Dictionary<string, int> data) 

    {

        var qq = new Dictionary<int, List<string>>();

        qq.Add(0,new List<string>());

        qq.Add(1,new List<string>());

        qq.Add(2,new List<string>());

        qq.Add(3,new List<string>());

        qq.Add(4,new List<string>());

        qq.Add(5,new List<string>());

        foreach (var ppl in data){

          var mysalary = ppl.Value;

            for (var i =0; i < list.Count ; i++){

                var currentMoney = list[i];

                //* 從最小開始 如果比這個小代表是這個級距

                if (mysalary < currentMoney){

                      ((List<string>)qq[i]).Add(ppl.Key);

                }

            }

        }

        return qq;

    }

    static void ShowDic(Dictionary<int, List<string>> dic)

    {

      foreach (var item in dic)

      {

        Console.WriteLine(item.Key + ":");

        foreach (var v in item.Value)

        {

          Console.WriteLine(v);

        }

        Console.WriteLine();

      }

    }

}