Scala で Project Euler Problem 15
scala> (21 to 40).product / (1 to 20).product res0: Int = 0 scala> (BigInt(21) to 40).product / (BigInt(1) to 20).product res1: scala.math.BigInt = 137846528820
scala> (21 to 40).product / (1 to 20).product res0: Int = 0 scala> (BigInt(21) to 40).product / (BigInt(1) to 20).product res1: scala.math.BigInt = 137846528820