diff --git a/buggy.py b/buggy.py
--- a/buggy.py
+++ b/buggy.py
@@ -11,7 +11,7 @@
     def findTheArrayConcVal(self, nums: List[int]) -> int:
         i = 0
         c = 0
-        j = len(nums)
+        j = len(nums) - 1
         while i <= j:
             if i == j:
                 c = c + nums[i]
