object ScalaMain_2014121701 extends App {

    var i = 0
    var sum = 0
    val x = while (i < 10) {
        i += 1
        sum += i
        sum
    }
    // while は式ではなく文
    assert(x == ())

    sum = 0
    val y = for (i <- 0 until 10) yield {
        sum += i
        sum
    }
    assert(y(9) == 45)

    println("done!! %s".format(new java.util.Date))
}