// Calculate the date of easter.
// This code is placed into the public domain.

#light

let easter year =
  if (year > 1582) then
    let g = (year % 19) + 1
    let c = (year / 100) + 1
    let x = (3 * c / 4) - 12
    let z = ((8 * c + 5) / 25) - 5
    let d = (5 * year / 4) - x - 10
    let e' = (11 * g + 20 + z - x) % 30
    let e = if (e' = 25 && g > 11) || (e' = 24) then e' + 1 else e'
    let m' = (44 - e)
    let m = if (m' < 21) then m' + 30 else m'
    let n = m + 7 - ((d + m) % 7)
    if (n > 31)
      then
        (n - 31, "April")
      else
        (n, "March")
   else
      failwith "Date out of range"