refactor

5 files changed, 25 insertions, 20 deletions

diff --git a/sort/bottomupmerge.go b/sort/bottomupmerge.go
index e7788bb..4891c04 100644
--- a/sort/bottomupmerge.go
+++ b/sort/bottomupmerge.go
@@ -10,7 +10,7 @@ func BottomUpMerge(a ds.ArrayList) ds.ArrayList {
 
 	for sz := 1; sz < length; sz = sz + sz {
 		for lo := 0; lo < length-sz; lo += sz + sz {
-			merge(a, aux, lo, lo+sz-1, min(lo+sz+sz-1, length-1))
+			merge(a, aux, lo, lo+sz, min(lo+sz+sz-1, length-1))
 		}
 	}
 
diff --git a/sort/merge.go b/sort/merge.go
index 86eb315..1f48c3a 100644
--- a/sort/merge.go
+++ b/sort/merge.go
@@ -20,7 +20,7 @@ func mergeSort(a, aux ds.ArrayList) {
 	mi := length / 2
 	mergeSort(a[0:mi], aux[0:mi])
 	mergeSort(a[mi:], aux[mi:])
-	merge(a, aux, 0, mi-1, length-1)
+	merge(a, aux, 0, mi, length-1)
 }
 
 func merge(a, aux ds.ArrayList, lo, mi, hi int) {
@@ -29,11 +29,11 @@ func merge(a, aux ds.ArrayList, lo, mi, hi int) {
 	}
 
 	i := lo
-	j := mi + 1
+	j := mi
 
 	for k := lo; k <= hi; k++ {
 		switch {
-		case i > mi:
+		case i >= mi:
 			a[k] = aux[j]
 			j++
 		case j > hi:
diff --git a/sort/parallelmerge.go b/sort/parallelmerge.go
index 577d7c1..f9a59a3 100644
--- a/sort/parallelmerge.go
+++ b/sort/parallelmerge.go
@@ -6,31 +6,38 @@ import (
 )
 
 func ParallelMerge(a ds.ArrayList) ds.ArrayList {
-	aux := make(ds.ArrayList, len(a))
-	parallelMerge(a, aux, 0, len(a)-1)
-
+	parallelMerge(a, make(ds.ArrayList, len(a)))
 	return a
 }
 
-func parallelMerge(a, aux ds.ArrayList, lo, hi int) {
-	mid := lo + (hi-lo)/2
-	defer merge(a, aux, lo, mid, hi)
+func parallelMerge(a, aux ds.ArrayList) {
+	length := len(a)
+	if length <= 1 {
+		return
+	}
 
-	if hi-lo <= 1000 {
-		//mergeSort(a, aux, lo, mid)
-		//mergeSort(a, aux, mid+1, hi)
+	mi := length / 2
+	if length < 1000 {
+		mergeSort(a[0:mi], aux[0:mi])
+		mergeSort(a[mi:], aux[mi:])
+		merge(a, aux, 0, mi, length-1)
 		return
 	}
 
 	var wg sync.WaitGroup
 	wg.Add(2)
+
 	go func() {
-		parallelMerge(a, aux, lo, mid)
+		parallelMerge(a[0:mi], aux[0:mi])
 		wg.Done()
 	}()
+
 	go func() {
-		parallelMerge(a, aux, mid+1, hi)
+		parallelMerge(a[mi:], aux[mi:])
 		wg.Done()
 	}()
+
 	wg.Wait()
+	merge(a, aux, 0, mi, length-1)
+	return
 }
diff --git a/sort/selection.go b/sort/selection.go
index 798fa27..781292a 100644
--- a/sort/selection.go
+++ b/sort/selection.go
@@ -17,9 +17,7 @@ func Selection(a ds.ArrayList) ds.ArrayList {
 		if min == i {
 			continue
 		}
-		tmp := a[i]
-		a[i] = a[min]
-		a[min] = tmp
+		a.Swap(i, min)
 	}
 
 	return a
diff --git a/sort/sort_test.go b/sort/sort_test.go
index f350b46..e3bda34 100644
--- a/sort/sort_test.go
+++ b/sort/sort_test.go
@@ -11,8 +11,8 @@ var benchResult ds.ArrayList
 var benchResultInt []int
 
 const minLength int = 1
-const maxLength int = 1000
-const maxSlowLength int = 1000
+const maxLength int = 10000
+const maxSlowLength int = 10000
 
 var arrayListCache map[string]ds.ArrayList