diff --git a/buggy.py b/buggy.py
--- a/buggy.py
+++ b/buggy.py
@@ -5,7 +5,7 @@
 for _ in range(N):
     l, r = map(int, input().split())
     L[l] += 1
-    L[r] -= -1
+    L[r] -= 1
 for i in range(num):
     L[i + 1] += L[i]
 
