Question

标题似乎有些混乱，但是我想做的很简单。我有2个列表，一个是：

List(12, 14, 16, 24, 26, 32, 36, 43, 44, 46, 52, 54, 56, 62, 66, 72, 74, 76)

第二个是：

List(11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 24, 25, 26, 27, 28, 29, 31, 32)

我想遍历第一个列表，看看第一个列表中是否存在一个值，该值将是前一个值和第二个列表中另一个值的总和。如果存在类似的值，则应将其与第二个列表中的值相加，并检查第一个列表中是否存在类似的值，依此类推，直到达到第一个列表中的最大可获取值。

例如：如果我们从第一个列表中获取值16，并继续将其与28相加，我们将得到值：

16, 44 and 72

或者：我们从第一个列表中选取24，继续向其中添加19并获取值：

24, 43 and 62

如果包括起始值在内，通过添加相同的数字找不到至少2个以上的值，则应该只获取列表中的下一个值并进行相同的计算。

任何帮助将不胜感激，我尝试使用 fold 和 reduce 函数，但无法使其正常工作。

编辑：

尝试使用Stream.iterate来完成这项工作，但这并没有真正作用

val iTried = Stream.iterate(0)(i => i + 1)
.takeWhile(i => coordinatesRows(i)
.toString exists coordinatesRows + valuesForDiag(i))

还尝试实现自己的功能：

def sortDiagonally(xs: List[Int]) ={
/**
**/
val start = xs.head
Stream.from(1).flatMap{ value =>
  xs exists (start + valuesForDiag == xs)
}

我仍在学习语言，所以我对Scala的所有来龙去脉都不熟悉。

编辑2：通过使用这两个列表，我希望获得以下输出：

List(List(16, 44, 72), List(24, 43, 62), List(32, 54, 76), List(36, 54, 72), List(12, 24, 36), List(12, 44, 76))

我还从第二个列表中删除了10, 20 and 30的值，因为它不应该在那里。

Answer 1

// Customizes read more link in excerpts
function new_excerpt_more($more) {
   global $post;
     return ‘ <strong> … on the edge of your seat? Read more! </strong> ‘; //you 
     can change this text to whatever you like
}
add_filter(‘excerpt_more’, ‘new_excerpt_more’);

返回：

  val vals = List(12, 14, 16, 24, 26, 32, 36, 43, 44, 46, 52, 54, 56, 62, 66, 72, 74, 76)
  val mods = List(10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32)

  def find(l: List[Int]): Set[Int] = l match {

    case Nil => Set.empty[Int]
    case x :: xs =>
      xs.filter{
        i => mods.exists(j => (i - x) % j == 0)
      }.toSet ++ find(xs)

  }

  find(vals)

所有匹配值：

Set(56, 24, 52, 46, 74, 32, 44, 54, 76, 66, 72, 43, 26, 36, 62)

返回：

  def find(l: List[Int]): List[(Int, Int, Int)] = l match {

    case Nil => Nil
    case x :: xs =>
     xs.flatMap{
       i => mods.collect{  case j if (i - x) % j == 0 => (x, i, j) }
     } ++ find(xs)
  }

  println(find(vals))

最后

List((12,24,12), (12,26,14), (12,32,10), (12,32,20), (12,36,12), (12,36,24), (12,43,31), (12,44,16), (12,44,32), (12,46,17), (12,52,10), (12,52,20), (12,54,14), (12,54,21), (12,56,11), (12,56,22), (12,62,10), (12,62,25), (12,66,18), (12,66,27), (12,72,10), (12,72,12), (12,72,15), (12,72,20), (12,72,30), (12,74,31), (12,76,16), (12,76,32), (14,24,10), (14,26,12), (14,32,18), (14,36,11), (14,36,22), (14,43,29), (14,44,10), (14,44,15), (14,44,30), (14,46,16), (14,46,32), (14,52,19), (14,54,10), (14,54,20), (14,56,14), (14,56,21), (14,62,12), (14,62,16), (14,62,24), (14,66,13), (14,66,26), (14,72,29), (14,74,10), (14,74,12), (14,74,15), (14,74,20), (14,74,30), (14,76,31), (16,26,10), (16,32,16), (16,36,10), (16,36,20), (16,43,27), (16,44,14), (16,44,28), (16,46,10), (16,46,15), (16,46,30), (16,52,12), (16,52,18), (16,54,19), (16,56,10), (16,56,20), (16,62,23), (16,66,10), (16,66,25), (16,72,14), (16,72,28), (16,74,29), (16,76,10), (16,76,12), (16,76,15), (16,76,20), (16,76,30), (24,36,12), (24,43,19), (24,44,10), (24,44,20), (24,46,11), (24,46,22), (24,52,14), (24,52,28), (24,54,10), (24,54,15), (24,54,30), (24,56,16), (24,56,32), (24,62,19), (24,66,14), (24,66,21), (24,72,12), (24,72,16), (24,72,24), (24,74,10), (24,74,25), (24,76,13), (24,76,26), (26,36,10), (26,43,17), (26,44,18), (26,46,10), (26,46,20), (26,52,13), (26,52,26), (26,54,14), (26,54,28), (26,56,10), (26,56,15), (26,56,30), (26,62,12), (26,62,18), (26,66,10), (26,66,20), (26,72,23), (26,74,12), (26,74,16), (26,74,24), (26,76,10), (26,76,25), (32,43,11), (32,44,12), (32,46,14), (32,52,10), (32,52,20), (32,54,11), (32,54,22), (32,56,12), (32,56,24), (32,62,10), (32,62,15), (32,62,30), (32,66,17), (32,72,10), (32,72,20), (32,74,14), (32,74,21), (32,76,11), (32,76,22), (36,46,10), (36,52,16), (36,54,18), (36,56,10), (36,56,20), (36,62,13), (36,62,26), (36,66,10), (36,66,15), (36,66,30), (36,72,12), (36,72,18), (36,74,19), (36,76,10), (36,76,20), (43,54,11), (43,56,13), (43,62,19), (43,66,23), (43,72,29), (43,74,31), (43,76,11), (44,54,10), (44,56,12), (44,62,18), (44,66,11), (44,66,22), (44,72,14), (44,72,28), (44,74,10), (44,74,15), (44,74,30), (44,76,16), (44,76,32), (46,56,10), (46,62,16), (46,66,10), (46,66,20), (46,72,13), (46,72,26), (46,74,14), (46,74,28), (46,76,10), (46,76,15), (46,76,30), (52,62,10), (52,66,14), (52,72,10), (52,72,20), (52,74,11), (52,74,22), (52,76,12), (52,76,24), (54,66,12), (54,72,18), (54,74,10), (54,74,20), (54,76,11), (54,76,22), (56,66,10), (56,72,16), (56,74,18), (56,76,10), (56,76,20), (62,72,10), (62,74,12), (62,76,14), (66,76,10))

返回：

  def find(l: List[Int]): List[List[Int]] = l match {

    case Nil => Nil
    case x :: xs =>
      mods.map {
        mod => x :: xs.collect { case c if (c - x) % mod == 0 => c }
      }.filter(_.size > 1) ++ find(xs)
  }

  find(vals)

在列表中查找一个值，该值等于上一个值与另一个列表中另一个值的和

1 个答案: