#!/usr/bin/perl -w

  use strict;
  use Calendar::Simple;

  my @months = qw(January February March April May June July August
                  September October November December);

  my $mon = shift || (localtime)[4] + 1;
  my $yr  = shift || (localtime)[5] + 1900;

  my @month = calendar($mon, $yr);

  print "\n$months[$mon -1] $yr\n\n";
  print "Su Mo Tu We Th Fr Sa\n";
  foreach (@month) {
    print map { $_ ? sprintf "%2d ", $_ : '   ' } @$_;
    print "\n";
  }