小编roc*_*kme的帖子

在spark中，我们可以轻松地使用map reduce来计算单词出现时间，并使用sort来获取前k个常见单词，

// Sort locally inside node, keep only top-k results,
// no network communication

val partialTopK = wordCount.mapPartitions(it => {
    val a = it.toArray
    a.sortBy(-_._2).take(10).iterator
}, true)


// Collect local top-k results, faster than the naive solution

val collectedTopK = partialTopK.collect
collectedTopK.size


// Compute global top-k at master,
// no communication, everything done on the master node

val topK = collectedTopK.sortBy(-_._2).take(10)

但是我想知道是否有更好的解决方案，根本避免排序？

 def balance(chars: List[Char]): Boolean = {
    if (chars.isEmpty == true) true
       else transCount(chars, 0)

 def transCount(chars: List[Char], pro: Int): Boolean = {
  var dif = pro
  chars match {
    case "(" :: Nil => false
    case ")" :: Nil => dif -= 1; if (dif == 0) true else false
    case _ :: Nil => if (dif == 0) true else false

    case "(" :: tail => dif += 1
      transCount(tail, dif)
    case ")" :: tail => dif -= 1; …

var reserve=prefinishedTask%15;

var num = "<?php echo $_SESSION['picture'][reserve]; ?>";

$_SESSION['picture']是一个整数数组,我正在尝试使用索引保留来获取其中一个.目前代码不起作用.

如果我改成它

 var num = "<?php echo $_SESSION['picture'][1]; ?>";

它可以工作,但我需要在数组中使用不同的索引,那么如何修复代码呢？最好,