Factorial

Example

import scala.language.postfixOps // don't forget this import // don't forget this import
import slash.Factorial.!
for (x:Int <- Seq(1, 2, 3, 4, 8, 16, 32, 64, 100)) {
  println(s"${x}! = ${x!}")
}
// 1! = 1
// 2! = 2
// 3! = 6
// 4! = 24
// 8! = 40320
// 16! = 20922789888000
// 32! = 263130836933693530167218012160000000
// 64! = 126886932185884164103433389335161480802865516174545192198801894375214704230400000000000000
// 100! = 93326215443944152681699238856266700490715968264381621468592963895217599993229915608941463976156518286253697920827223758251185210916864000000000000000000000000