import java.util.*

fun main(args: Array<String>) {
  val sc = Scanner(System.`in`)
  val a = sc.nextLong()
  val b = sc.nextLong()
  val c = sc.nextLong()

  val abc = mutableListOf<Long>()
  abc.add(a)
  abc.add(b)
  abc.add(c)

  for (i in abc) {
    if (i % 2L == 0L) {
      println(0)
      return
    }
  }

  val sort = abc.sorted()
  val f = sort.get(0)
  val s = sort.get(1)
  val t = sort.get(2)

  val tmp = t / 2L

  val red = tmp * f * s
  val blue = (t - tmp) * f * s

  println(blue - red)

}
