Built-in method

閏年
閏年 在 Scala 中 
import java.time.{Year}

object Leap {
  def leapYear(year: Int): Boolean =
    Year.of(year).isLeap()
}

This may be considered a "wicked cheat" for this exercise, by simply passing the year into the isLeap() method of the Year class. Although it is not in the spirit of this exercise, isLeap() would be the idiomatic way to determine if a year is a leap year in the "real world".

2026年09月25日 · 覺得有幫助嗎？

Scala 中 閏年 的其他解法

我們社群解決這個練習的其他方式
def leapYear(year: Int): Boolean =
  year % 4 == 0 && (year % 100 != 0 || year % 400 == 0)
Boolean chain

Use a chain of boolean expressions. 

def leapYear(year: Int): Boolean =
  if (year % 100 == 0) year % 400 == 0
  else year % 4 == 0
Ternary expression

Use a ternary expression of boolean conditions. 

def leapYear(year: Int): Boolean =
  (year % 4, year % 100, year % 400) match {
    case (_, _, 0) => true
    case (_, 0, _) => false
    case (0, _, _) => true
    case (_, _, _) => false
  }
match on a tuple

Use a match on a tuple made from boolean expressions. 

import java.time.{LocalDate, Month}

object Leap {
  def leapYear(year: Int): Boolean =
    LocalDate.of(year, Month.FEBRUARY, 28).plusDays(1).getDayOfMonth() == 29
}
LocalDate plusDays

Use LocalDate plusDays.