func is_long_year(year) {
    Date.parse("#{year}-12-28", "%Y-%m-%d").week == 53
}

say (  "Long years in the 20th century:\n", (1900..^2000).grep(is_long_year))
say ("\nLong years in the 21st century:\n", (2000..^2100).grep(is_long_year))
say ("\nLong years in the 22nd century:\n", (2100..^2200).grep(is_long_year))