diff --git a/buggy.py b/buggy.py
--- a/buggy.py
+++ b/buggy.py
@@ -27,7 +27,7 @@
         if row[i] == 1:
             e_s = i
             break
-    if f_s and e_s and any(row[i] == 0 for i in range(f_s, e_s)):
+    if f_s != None and e_s != None and any(row[i] == 0 for i in range(f_s, e_s)):
         print("Yes")
     else:
         print("No")
