Question

如何对Scala中集合进行排序

Answer 1

如何对Map中的Key或Value进行排序
其实很简单代码如下：
// sort by key can use sorted
m.toList.sorted foreach {
case (key,value) =>
println(key + " = " + value)
}
-2 = 5
-1 = -4
0 = -16
1 = 2
2 = 6
5 = 9
// sort by value
m.toList sortBy ( _._2 ) foreach {
case (key,value) =>
println(key + " = " + value)
}
0 = -16
-1 = -4
1 = 2
-2 = 5
2 = 6
5 = 9

Answer 2

val list1 = List(1, 2, 3, 4, 5, 6)
list1.sorted
list1.sortWith(_ > _)
val sortedSet = scala.collection.immutable.SortedSet(2, 3, 4, 5, 1)