diff options
-rw-r--r-- | Scala/sandbox/0-main.scala | 1 | ||||
-rw-r--r-- | Scala/sandbox/10-merge-sort.scala | 25 |
2 files changed, 26 insertions, 0 deletions
diff --git a/Scala/sandbox/0-main.scala b/Scala/sandbox/0-main.scala index 2616f8f..1061f50 100644 --- a/Scala/sandbox/0-main.scala +++ b/Scala/sandbox/0-main.scala @@ -12,5 +12,6 @@ object Main extends App { Variance.run PatternMatching.run Lists.run + MergeSort.run } diff --git a/Scala/sandbox/10-merge-sort.scala b/Scala/sandbox/10-merge-sort.scala new file mode 100644 index 0000000..92296e2 --- /dev/null +++ b/Scala/sandbox/10-merge-sort.scala @@ -0,0 +1,25 @@ +object MergeSort +{ + + def msort(xs: List[Int]): List[Int] = { + val n = xs.length/2 + if (n==0) xs + else { + def merge(xs: List[Int], ys: List[Int]): List[Int] = (xs, ys) match { + case (Nil, ys) => ys + case (xs, Nil) => xs + case (x :: xs1, y :: ys1) => { + if (x < y) x :: merge(xs1, ys) + else y :: merge(xs, ys1) + } + } + val (fst, snd) = xs splitAt n + merge(msort(fst), msort(snd)) + } + } + + def run = { + println("MergeSort") + println(msort(List(2, 8, -2, 9, 2, 6, 0, 7, 1))) + } +} |