#!/usr/bin/ruby

#
## https://rosettacode.org/wiki/Find_the_last_Sunday_of_each_month
#

require('DateTime');

var year = (ARGV[0] \\ 2015);

range(1, 12).each { |i|
    var date = %s'DateTime'.last_day_of_month(
        year  => year,
        month => i,
    );

    while (date.dow != 7) {
        date = date.subtract(days => 1);
    };

    say date.ymd;
}