diff --git a/lang/base.go b/lang/base.go
index c0df78f8..d5aff651 100644
--- a/lang/base.go
+++ b/lang/base.go
@@ -459,9 +459,8 @@ func (l baseLang) generateTestCasesContent(q *leetcode.QuestionData) string {
 	// Assume all questions output are single.
 	var tc TestCases
 	for i := 0; i < len(cases) && i/argsNum < len(outputs); i += argsNum {
-		tc.Cases = append(
-			tc.Cases, TestCase{
-				No:     i/argsNum + 1,
+		tc.AddCase(
+			TestCase{
 				Input:  cases[i : i+argsNum],
 				Output: outputs[i/argsNum],
 			},
diff --git a/lang/judge.go b/lang/judge.go
index dc113588..08486ad9 100644
--- a/lang/judge.go
+++ b/lang/judge.go
@@ -10,8 +10,9 @@ import (
 	"github.com/goccy/go-json"
 	strip "github.com/grokify/html-strip-tags-go"
 
-	"github.com/j178/leetgo/leetcode"
 	goutils "github.com/j178/leetgo/testutils/go"
+
+	"github.com/j178/leetgo/leetcode"
 )
 
 type JudgeResult interface {
diff --git a/lang/testcase.go b/lang/testcase.go
index ce925af8..e6114219 100644
--- a/lang/testcase.go
+++ b/lang/testcase.go
@@ -8,8 +8,9 @@ import (
 	"strconv"
 	"strings"
 
-	"github.com/j178/leetgo/leetcode"
 	goutils "github.com/j178/leetgo/testutils/go"
+
+	"github.com/j178/leetgo/leetcode"
 	"github.com/j178/leetgo/utils"
 )
 
@@ -170,7 +171,7 @@ func ParseTestCases(q *leetcode.QuestionData, f *FileOutput) (TestCases, error)
 	)
 	lines := utils.SplitLines(content)
 	for _, line := range lines {
-		line := strings.TrimSpace(line)
+		line = strings.TrimSpace(line)
 		switch {
 		case line == "":
 			continue