diff --git a/buggy.py b/buggy.py
--- a/buggy.py
+++ b/buggy.py
@@ -5,7 +5,7 @@
 
 ans = "Yes"
 for i in range(1, max(cnt) + 1):
-    if cnt.count(i) != 2:
+    if (cnt.count(i) != 2) and (cnt.count(i) != 0):
         ans = "No"
         break
 print(ans)
