1 files changed, 37 insertions, 0 deletions
diff --git a/sort/merge2.go b/sort/merge2.go
new file mode 100644
index 0000000..774c3c5
--- /dev/null
+++ b/sort/merge2.go
@@ -0,0 +1,37 @@
+package sort
+
+import (
+	"algorithms/ds"
+	"sync"
+)
+
+// Merge2 is a parallelized version of Merge
+func Merge2(a ds.ArrayList) ds.ArrayList {
+	aux := make(ds.ArrayList, len(a))
+	mergeSort2(a, aux, 0, len(a)-1)
+
+	return a
+}
+
+func mergeSort2(a, aux ds.ArrayList, lo, hi int) {
+	mid := lo + (hi-lo)/2
+	defer merge(a, aux, lo, mid, hi)
+
+	if hi-lo <= 1000 {
+		mergeSort(a, aux, lo, mid)
+		mergeSort(a, aux, mid+1, hi)
+		return
+	}
+
+	var wg sync.WaitGroup
+	wg.Add(2)
+	go func() {
+		mergeSort2(a, aux, lo, mid)
+		wg.Done()
+	}()
+	go func() {
+		mergeSort2(a, aux, mid+1, hi)
+		wg.Done()
+	}()
+	wg.Wait()
+}