using System;

class CaseDemo{

  public static void Main(){
    int month = 2,
        numberOfDays;

    switch(month){
      case 1: case 3: case 5: case 7: case 8: case 10: case 12:
        numberOfDays = 31; break;
      case 4: case 6: case 9: case 11:
        numberOfDays = 30; break;        
      case 2: 
        numberOfDays = 28; break;     // or 29
      default: 
        throw new Exception("Problems");
    }

    Console.WriteLine(numberOfDays);  // prints 28
  }

}