path: root/test/files/run/priorityQueue.scala

import scala.collection.mutable.PriorityQueue






// populate a priority queue a few different ways and make sure they all seem equal
object Test {

  def main(args: Array[String]) {
    testInsertionsAndEqualities
    testIntensiveEnqueueDequeue
    testIndexing
    testTails
    testInits
    testFilters
    testDrops
    testUpdates
    testEquality
    testSeq
  }

  def testInsertionsAndEqualities {
    import scala.util.Random.nextInt
    val pq1 = new PriorityQueue[String]
    val pq2 = new PriorityQueue[String]
    val pq3 = new PriorityQueue[String]
    val pq4 = new PriorityQueue[String]

    val strings = (1 to 20).toList map (i => List.fill((Math.abs(nextInt % 20)) + 1)("x").mkString)

    pq1 ++= strings
    pq2 ++= strings.reverse
    for (s <- strings) pq3 += s
    for (s <- strings.reverse) pq4 += s

    val pqs = List(pq1, pq2, pq3, pq4, pq1.clone, pq2.clone)

    for (queue1 <- pqs ; queue2 <- pqs) {
      assert(queue1 == queue2)
      assert(queue1.max == queue2.max)
    }

    assertPriority(pq1)
  }

  def testIndexing {
    val pq = new PriorityQueue[Char]
    "The quick brown fox jumps over the lazy dog".foreach(pq += _)

    // val iter = pq.iterator
    // while (iter.hasNext) println("`" + iter.next + "`")
    assert(pq(0) == 'z')
    assert(pq(1) == 'y')
    assert(pq(2) == 'x')
    assert(pq(3) == 'w')
    assert(pq(4) == 'v')
    assert(pq(5) == 'u')
    assert(pq(7) == 't')
    assert(pq(8) == 's')
    assert(pq(9) == 'r')
    assert(pq(10) == 'r')

    pq.clear
    "abcdefghijklmnopqrstuvwxyz".foreach(pq += _)
    for (i <- 0 until 26) assert(pq(i) == ('z' - i))

    val intpq = new PriorityQueue[Int]
    val intlst = new collection.mutable.ArrayBuffer ++ (0 until 100)
    val random = new util.Random(101)
    while (intlst.nonEmpty) {
      val idx = random.nextInt(intlst.size)
      intpq += intlst(idx)
      intlst.remove(idx)
    }
    for (i <- 0 until 100) assert(intpq(i) == (99 - i))
  }

  def testTails {
    val pq = new PriorityQueue[Int]
    for (i <- 0 until 10) pq += i * 4321 % 200

    assert(pq.size == 10)
    assert(pq.nonEmpty)

    val tailpq = pq.tail
    // pq.printstate
    // tailpq.printstate
    assert(tailpq.size == 9)
    assert(tailpq.nonEmpty)
    assertPriorityDestructive(tailpq)
  }

  def assertPriorityDestructive[A](pq: PriorityQueue[A])(implicit ord: Ordering[A]) {
    import ord._
    var prev: A = null.asInstanceOf[A]
    while (pq.nonEmpty) {
      val curr = pq.dequeue
      if (prev != null) assert(curr <= prev)
      prev = curr
    }
  }

  def assertPriority[A](pq: PriorityQueue[A])(implicit ord: Ordering[A]) {
    import ord._
    var prev: A = null.asInstanceOf[A]
    val iter = pq.iterator
    while (iter.hasNext) {
      val curr = iter.next
      if (prev != null) assert(curr <= prev)
      prev = curr
    }
  }

  def testInits {
    val pq = new PriorityQueue[Long]
    for (i <- 0 until 20) pq += (i + 313) * 111 % 300

    assert(pq.size == 20)

    val initpq = pq.init
    assert(initpq.size == 19)
    assertPriorityDestructive(initpq)
  }

  def testFilters {
    val pq = new PriorityQueue[String]
    for (i <- 0 until 100) pq += "Some " + (i * 312 % 200)

    val filpq = pq.filter(_.indexOf('0') != -1)
    assertPriorityDestructive(filpq)
  }

  def testIntensiveEnqueueDequeue {
    val pq = new PriorityQueue[Int]

    testIntensive(1000, pq)
    pq.clear
    testIntensive(200, pq)
  }

  def testIntensive(sz: Int, pq: PriorityQueue[Int]) {
    val lst = new collection.mutable.ArrayBuffer[Int] ++ (0 until sz)
    val rand = new util.Random(7)
    while (lst.nonEmpty) {
      val idx = rand.nextInt(lst.size)
      pq.enqueue(lst(idx))
      lst.remove(idx)
      if (rand.nextDouble < 0.25 && pq.nonEmpty) pq.dequeue
      assertPriority(pq)
    }
  }

  def testDrops {
    val pq = new PriorityQueue[Int]
    pq ++= (0 until 100)
    val droppq = pq.drop(50)
    assertPriority(droppq)

    pq.clear
    pq ++= droppq
    assertPriorityDestructive(droppq)
    assertPriority(pq)
    assertPriorityDestructive(pq)
  }

  def testUpdates {
    val pq = new PriorityQueue[Int]
    pq ++= (0 until 36)
    assertPriority(pq)

    pq(0) = 100
    assert(pq(0) == 100)
    assert(pq.dequeue == 100)
    assertPriority(pq)

    pq.clear

    pq ++= (1 to 100)
    pq(5) = 200
    assert(pq(0) == 200)
    assert(pq(1) == 100)
    assert(pq(2) == 99)
    assert(pq(3) == 98)
    assert(pq(4) == 97)
    assert(pq(5) == 96)
    assert(pq(6) == 94)
    assert(pq(7) == 93)
    assert(pq(98) == 2)
    assert(pq(99) == 1)
    assertPriority(pq)

    pq(99) = 450
    assert(pq(0) == 450)
    assert(pq(1) == 200)
    assert(pq(99) == 2)
    assertPriority(pq)

    pq(1) = 0
    assert(pq(1) == 100)
    assert(pq(99) == 0)
    assertPriority(pq)
    assertPriorityDestructive(pq)
  }

  def testEquality {
    val pq1 = new PriorityQueue[Int]
    val pq2 = new PriorityQueue[Int]

    pq1 ++= (0 until 50)
    var i = 49
    while (i >= 0) {
      pq2 += i
      i -= 1
    }
    assert(pq1 == pq2)
    assertPriority(pq2)

    pq1 += 100
    assert(pq1 != pq2)
    pq2 += 100
    assert(pq1 == pq2)
    pq2 += 200
    assert(pq1 != pq2)
    pq1 += 200
    assert(pq1 == pq2)
    assertPriorityDestructive(pq1)
    assertPriorityDestructive(pq2)
  }

  def testSeq {
    val pq = new PriorityQueue[Int]
    pq ++= (0 until 100)

    val (p1, p2) = pq.partition(_ < 50)
    assertPriorityDestructive(p1)
    assertPriorityDestructive(p2)

    val spq = pq.slice(25, 75)
    assertPriorityDestructive(spq)

    pq.clear
    pq ++= (0 until 10)
    pq += 5
    //val ind = pq.lastIndexWhere(_ == 5)
    //println(ind)
    //println(pq)
    //assert(ind == 5)
    //assertPriorityDestructive(pq)

    //pq.clear
    //pq ++= (0 until 10)
  }

}