#!/usr/bin/perl -w

use strict;

use Time::Local qw( timelocal );

my $year = 2001;
my $day = 200;

my $year_sec = timelocal(0, 0, 0, 1, 0, $year-1900);
my $new_sec = $year_sec + ($day-1) * 60 * 60 *24;

print localtime($new_sec)."\n";

my ($theday, $month) = (localtime($new_sec))[3,4];
$month++;

print "day = $theday, month = $month\n";