add stooge sort (#774)

Author: lyqio

sort/sorts_test.go

@@ -198,6 +198,10 @@ func TestOddEvenSort(t *testing.T) {
 	testFramework(t, sort.OddEvenSort[int])
 }
 
+func TestStooge(t *testing.T) {
+	testFramework(t, sort.Stooge[int])
+}
+
 // END TESTS
 
 func benchmarkFramework(b *testing.B, f func(arr []int) []int) {
@@ -340,3 +344,7 @@ func BenchmarkTimsort(b *testing.B) {
 func BenchmarkCircle(b *testing.B) {
 	benchmarkFramework(b, sort.Circle[int])
 }
+
+func BenchmarkStooge(b *testing.B) {
+	benchmarkFramework(b, sort.Stooge[int])
+}

sort/stooge_sort.go

@@ -0,0 +1,34 @@
+// implementation of the Stooge sort
+// more info at https://en.wikipedia.org/wiki/Stooge_sort
+// worst-case time complexity    O(n^2.709511)
+// worst-case space complexity   O(n)
+
+package sort
+
+import (
+	"github.com/TheAlgorithms/Go/constraints"
+
+	// math imported for floor division
+	"math"
+)
+
+func innerStooge[T constraints.Ordered](arr []T, i int32, j int32) []T {
+	if arr[i] > arr[j] {
+		arr[i], arr[j] = arr[j], arr[i]
+	}
+	if (j - i + 1) > 2 {
+		t := int32(math.Floor(float64(j-i+1) / 3.0))
+		arr = innerStooge(arr, i, j-t)
+		arr = innerStooge(arr, i+t, j)
+		arr = innerStooge(arr, i, j-t)
+	}
+	return arr
+}
+
+func Stooge[T constraints.Ordered](arr []T) []T {
+	if len(arr) == 0 {
+		return arr
+	}
+
+	return innerStooge(arr, 0, int32(len(arr)-1))
+}