bugfix

src/routes/api/add.js

@@ -8,7 +8,7 @@ router.post('/', (req, res) => {
 });
 
 router.get('/:a/:b', (req, res) => {
-    res.json({ ret: req.params.a + req.params.b });
+    res.json({ ret: Number(req.params.a) + Number(req.params.b) });
 });
 
 module.exports = router;