#!/usr/bin/env perl -l

use strict;
use warnings;

use Time::Piece;

my $month = 10;
my $year = 2013;

for (1 .. 7) { # Time::Piece->wday returns: Sunday = 1, ..., Saturday = 7
    print +($_ - Time::Piece->strptime("$year$month" . '01', '%Y%m%d')->wday) % 7 + 1;
}