use warnings;
use strict;

use Date::Calc qw( Week_of_Year Monday_of_Week Month_to_Text );

# Date::Calc uses 1 = Monday, ... 7 = Sunday

foreach my $date ( 1 .. 20 )
{
    my $week = Week_of_Year( 2005, 4, $date ); # see docs for caveats

    my ( $year, $month, $day ) = Monday_of_Week( $week, 2005 );

    print "The Monday before April $date was ",
           Month_to_Text( $month ), " $day\n";
}