diff --git a/buggy.py b/buggy.py
--- a/buggy.py
+++ b/buggy.py
@@ -22,7 +22,7 @@
     ans = [0]
     for i in range(n):
         if len(s) == 0:
-            print(-1)
+            print("No")
             return
         for ss in s:
             break
