# include <stdio.h>

//
//  Program 14.1, Stephen Kochan, Programming in C.
//
enum month_type 
{
  january = 1, february, march, april, may, june,
  july, august, september, october, november, december 
};

int main ( void );

int main ( void )
{
  enum month_type month;
  int days;

  printf ( "Enter a month number: " );
  scanf ( "%i", &month );

  switch ( month )
  {
    case january:
    case march:
    case may:
    case july:
    case august:
    case october:
    case december:
      days = 31;
      break;

    case april:
    case june:
    case september:
    case november:
      days = 30;
      break;

    case february:
      days = 28;
      break;

    default:
      printf ( "Bad month number\n" );
      days = 0;
      break;
  }

  if ( days != 0 )
  {
    printf ( "Number of days is %i\n", days );
  }

  if ( month == february )
  {
    printf ( "...or 29, if it's a leap year.\n" );
  }

  return 0;
}