Scala で Project Euler Problem 19
scala> def weekday(year:Int, month:Int, d:Int) = { | var y = year | var m = month | if (m == 1 || m == 2) { | y -= 1 | m += 12 | } | (y + y / 4 - y / 100 + y / 400 + (13 * m + 8) / 5 + d) % 7 | } weekday: (year: Int, month: Int, d: Int)Int
scala> weekday(2013, 2, 1) res0: Int = 5
scala> var i = 0 i: Int = 0 scala> for (y <- 1901 to 2000; m <- 1 to 12) { | if (weekday(y, m, 1) == 0) i += 1 | } scala> i res2: Int = 171