find.scala

def find(a: Array[Array[Int]], v: Int): (Int, Int) = {
  var i = 0
  while(i < a.length) {
    val aa = a(i)
    var j = 0
    while(j < aa.length) {
      if(aa(j) == v) return (i, j)
      j += 1
    }
    i += 1
  }
  null
}
def find2(a: Array[Array[Int]], v: Int): (Int, Int) = {
  def f(i: Int): (Int, Int) = {
    if(i < a.length) {
      val aa = a(i)
      def g(j: Int): (Int, Int) = {
        if(j < aa.length) {
          if(aa(j) == v) (i, j) else g(j+1)
        } else null
      }
      val r = g(0)
      if(r ne null) r else f(i+1)
    } else null
  }
  f(0)
}
case object Escape extends RuntimeException with scala.util.control.NoStackTrace
def find3(a: Array[Array[Int]], v: Int): (Int, Int) = {
  var x, y = 0
  try {
    var i = 0
    while(i < a.length) {
      val aa = a(i)
      var j = 0
      while(j < aa.length) {
        if(aa(j) == v) {
          x = i
          y = j
          throw Escape
        }
        j += 1
      }
      i += 1
    }
    null
  } catch { 
    case Escape => (x, y)
  }
}
val a = Array(Array(1,2,3), Array(1,2,3), Array(1,2,3), Array(1,2,3), Array(1,2,3), Array(1,2,3), Array(1,2,3), Array(1,2,3), Array(1,2,3), Array(1,2,3), Array(1,2,3), Array(1,2,3), Array(1,2,3), Array(1,2,3), Array(1,2,3), Array(1,2,3), Array(1,2,3), Array(1,2,3), Array(1,2,3), Array(1,2,3), Array(42))
var i = 0
while(i < 20) {
  val t0 = System.currentTimeMillis
  var c = 0
  var r: AnyRef = null
  while(c < 10000000) {
    r = find2(a, 42)
    c += 1
  }
  val t1 = System.currentTimeMillis
  println(t1-t0)
  i += 1
}