Refactor code, added new checkXu test cases(9 latterns)

pkg/environment/environment_test.go

@@ -0,0 +1,17 @@
+package pkg
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestPrint(t *testing.T) {
+	var env environment
+	env.Print()
+}
+
+func TestPatternNormalization(t *testing.T) {
+	var env environment
+	handTiles := env.PatternNormalization()
+	fmt.Println(handTiles)
+}