feat: added merge sort code implementation in golang with unit test c…

Golang/Merge Sort Algorithm/go.mod

@@ -0,0 +1,3 @@
+module github.com/nikzayn/letsdocode
+
+go 1.21.1

Golang/Merge Sort Algorithm/main.go

@@ -0,0 +1,51 @@
+package main
+
+import "fmt"
+
+// MergeSort function
+func MergeSort(arr []int) []int {
+	if len(arr) <= 1 {
+		return arr
+	}
+
+	mid := len(arr) / 2
+	left := arr[:mid]
+	right := arr[mid:]
+
+	left = MergeSort(left)
+	right = MergeSort(right)
+
+	return merge(left, right)
+}
+
+// merge function
+func merge(left, right []int) []int {
+	result := make([]int, 0)
+
+	for len(left) > 0 || len(right) > 0 {
+		if len(left) > 0 && len(right) > 0 {
+			if left[0] <= right[0] {
+				result = append(result, left[0])
+				left = left[1:]
+			} else {
+				result = append(result, right[0])
+				right = right[1:]
+			}
+		} else if len(left) > 0 {
+			result = append(result, left[0])
+			left = left[1:]
+		} else if len(right) > 0 {
+			result = append(result, right[0])
+			right = right[1:]
+		}
+	}
+
+	return result
+}
+
+func main() {
+	arr := []int{12, 11, 13, 5, 6, 7}
+	fmt.Println("Unsorted array:", arr)
+	sortedArr := MergeSort(arr)
+	fmt.Println("Sorted array:", sortedArr)
+}

Golang/Merge Sort Algorithm/main_test.go

@@ -0,0 +1,50 @@
+package main
+
+import (
+	"math/rand"
+	"reflect"
+	"testing"
+	"time"
+)
+
+func TestMergeSort(t *testing.T) {
+	// Test case 1: Sorting an empty slice should return an empty slice.
+	arr1 := []int{}
+	expected1 := []int{}
+	result1 := MergeSort(arr1)
+	if !reflect.DeepEqual(result1, expected1) {
+		t.Errorf("Test case 1 failed. Expected: %v, got: %v", expected1, result1)
+	}
+
+	// Test case 2: Sorting a slice with one element should return the same slice.
+	arr2 := []int{5}
+	expected2 := []int{5}
+	result2 := MergeSort(arr2)
+	if !reflect.DeepEqual(result2, expected2) {
+		t.Errorf("Test case 2 failed. Expected: %v, got: %v", expected2, result2)
+	}
+
+	// Test case 3: Sorting a slice with multiple elements.
+	arr3 := []int{12, 11, 13, 5, 6, 7}
+	expected3 := []int{5, 6, 7, 11, 12, 13}
+	result3 := MergeSort(arr3)
+	if !reflect.DeepEqual(result3, expected3) {
+		t.Errorf("Test case 3 failed. Expected: %v, got: %v", expected3, result3)
+	}
+}
+
+func generateRandomSlice(size int) []int {
+	rand.Seed(time.Now().UnixNano())
+	arr := make([]int, size)
+	for i := 0; i < size; i++ {
+		arr[i] = rand.Intn(1000) // Generate random numbers between 0 and 999
+	}
+	return arr
+}
+
+func BenchmarkMergeSort(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		input := generateRandomSlice(1000) // Adjust the slice size as needed
+		MergeSort(input)
+	}
+}