プレミアムフライデーを求める記述をKotlinで書いてみた - Qiita

import java.time.* import java.time.Month.* import java.time.format.DateTimeFormatter import java.time.temporal.TemporalAdjusters object PremiumFridayKotlin { @JvmStatic fun main(args: Array<String>) { val years = intArrayOf(2017, 2018, 2019, 2020) for (year in years) values() .filterNot { year == 2017 && it == JANUARY } .map { YearMonth.of(year, it) } .map { getMonthOfPremiumFriday(it) } .forEach