Built-in method

Leap
Leap in Scala 
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".

8th May 2024 · Found it useful?

Other Approaches to Leap in Scala

Other ways our community solved this exercise
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.