宿舍值日

using System;
public class OnDuty
{
 public static void Main()
 {
  int today;
        do
  {
   Console.WriteLine ("Please input what day it is today:\n\n1 2 3 4 5 6 7 will be ok.and -1 is quit");
   today=int.Parse (Console.ReadLine ());
   switch(today)
   {
    case 1:
     Console.WriteLine ("\nA is on duty today.He must make our room cleanly.");
     break;
    case 2:
     Console.WriteLine ("\nB is on duty today.He msut make our room cleanly.");
     break;
    case 3:
     Console.WriteLine ("\nC is on duty today.He msut make our room cleanly.");
     break;
    case 4:
     Console.WriteLine ("\nD is on duty today.He must make our room cleanly.");
     break;
    case 5:
     Console.WriteLine ("\nE is on duty today.He msut make our room cleanly.");
     break;
    case 6:
     Console.WriteLine ("\nF is on duty today.He must make our room cleanly.");
     break;
    case 7:
     Console.WriteLine ("\nG is on duty today.He must make our room cleanly.");
     break;
    case -1:
     break;
    default:
     Console.WriteLine ("Invalid input.Please retry:");
     break;
   }
  }while(today!=-1);
 }
}