diff --git a/leetcode_91_2/2020/0447/447. Number of Boomerangs.go b/leetcode_91_2/2020/0447/447. Number of Boomerangs.go
index eb78905..1100c6c 100644
--- a/leetcode_91_2/2020/0447/447. Number of Boomerangs.go	
+++ b/leetcode_91_2/2020/0447/447. Number of Boomerangs.go	
@@ -1,7 +1,5 @@
 package _447
 
-import "fmt"
-
 func numberOfBoomerangs(points [][]int) int {
 	res := 0
 	for i := 0; i < len(points); i++ {
@@ -10,7 +8,7 @@ func numberOfBoomerangs(points [][]int) int {
 			if i != j {
 				d := distanceCalc(points[i], points[j])
 				v, ok := distance[d]
-				fmt.Printf("d is %v\n", d)
+				//fmt.Printf("d is %v\n", d)
 				if ok { // 存在
 					res += 2 * v // (v+1) * v - [v * (v-1)] = 2 * v
 					distance[d] += 1
diff --git a/leetcode_91_2/2020/0447/447. Number of Boomerangs_test.go b/leetcode_91_2/2020/0447/447. Number of Boomerangs_test.go
index 72d6da3..8160cd2 100644
--- a/leetcode_91_2/2020/0447/447. Number of Boomerangs_test.go	
+++ b/leetcode_91_2/2020/0447/447. Number of Boomerangs_test.go	
@@ -16,4 +16,12 @@ func TestNumberOfBoomerangs(t *testing.T) {
 		}),
 		"must be 2",
 	)
+	assert.Equal(t, 2,
+		numberOfBoomerangs1([][]int{
+			{0, 0},
+			{1, 0},
+			{2, 0},
+		}),
+		"must be 2",
+	)
 }
diff --git a/topic/stack_queue/225. Implement Stack using Queues.go b/topic/stack_queue/225. Implement Stack using Queues.go
index 0b02546..efe615e 100644
--- a/topic/stack_queue/225. Implement Stack using Queues.go	
+++ b/topic/stack_queue/225. Implement Stack using Queues.go	
@@ -5,13 +5,6 @@ type MyStack struct {
 	Queue2 []int
 }
 
-func stackConstructor() MyStack {
-	return MyStack{
-		Queue1: make([]int, 0),
-		Queue2: make([]int, 0),
-	}
-}
-
 func (m *MyStack) Push(x int) {
 	if len(m.Queue2) != 0 {
 		m.Queue2 = append(m.Queue2, x)
diff --git a/topic/stack_queue/225. Implement Stack using Queues_test.go b/topic/stack_queue/225. Implement Stack using Queues_test.go
index e9341f5..d3b4b90 100644
--- a/topic/stack_queue/225. Implement Stack using Queues_test.go	
+++ b/topic/stack_queue/225. Implement Stack using Queues_test.go	
@@ -1,6 +1,10 @@
 package stack_queue
 
-import "testing"
+import (
+	"testing"
+
+	"github.com/bmizerany/assert"
+)
 
 func TestMyStack_Pop(t *testing.T) {
 	type fields struct {
@@ -41,3 +45,22 @@ func TestMyStack_Pop(t *testing.T) {
 		})
 	}
 }
+
+func TestMyStack(t *testing.T) {
+	m := &MyStack{}
+
+	assert.Equal(t, true, m.Empty())
+	// Test when Queue2 is empty
+	m.Push(1)
+	if len(m.Queue1) != 1 {
+		t.Errorf("Expected Queue1 length to be 1, got %d", len(m.Queue1))
+	}
+	assert.Equal(t, false, m.Empty())
+
+	m.Push(2)
+
+	assert.Equal(t, 2, m.Top())
+	assert.Equal(t, 2, m.Pop())
+	m.Push(3)
+	assert.Equal(t, 3, m.Top())
+}