diff --git a/day_02/program.py b/day_02/program.py
index a85eb07..f02822f 100755
--- a/day_02/program.py
+++ b/day_02/program.py
@@ -18,13 +18,13 @@ def get_report_entries(lines: list) -> list:
 def is_safe_single(reports: list) -> bool:
     increasing = True
     decreasing = True
-    for i in range(len(reports) - 1):
-        distance = abs(reports[i] - reports[i + 1])
+    for a, b in zip(reports, reports[1:]):
+        distance = abs(a - b)
         if distance == 0 or distance > 3:
             return False
-        if reports[i] > reports[i + 1]:
+        if a > b:
             increasing = False
-        if reports[i] < reports[i + 1]:
+        if a < b:
             decreasing = False
     return increasing or decreasing