switch ($wday)
{
   case 0 { print "today is Sun"; }
   case 1 { print "today is Mon"; }
   case 2 { print "today is Tue"; }
   case 3 { print "today is Wed"; }
   case 4 { print "today is Thu"; }
   case 5 { print "today is Fri"; }
   case 6 { print "today is Sat"; }
}

   if   ($wday eq "0") { print "today is Sun"; }
   elsif($wday eq "1") { print "today is Mon"; }
   elsif($wday eq "2") { print "today is Tue"; }
   elsif($wday eq "3") { print "today is Wed"; }
   elsif($wday eq "4") { print "today is Thu"; }
   elsif($wday eq "5") { print "today is Fri"; }
   elsif($wday eq "6") { print "today is Sat"; }