diff --git a/4/cleanup.py b/4/cleanup.py
index 3b0f81a..8421353 100644
--- a/4/cleanup.py
+++ b/4/cleanup.py
@@ -6,6 +6,7 @@ def find_overlaps(sets: list) -> int:
     """
     count the number of sets that overlap
     """
+    # generate a list where ones correlate to intersecting pairs
     overlaps = [1 if set.intersection(*pair) else 0 for pair in sets]
     return sum(overlaps)
 
@@ -14,6 +15,7 @@ def find_subsets(sets: list) -> int:
     """
     count the number of sets that fully contain each other
     """
+    # generate a list where ones correlate to subsets of a and b
     subsets = [
         1 if pair[0].issubset(pair[1]) or pair[1].issubset(pair[0]) else 0
         for pair in sets
@@ -28,7 +30,7 @@ def parse_input(data: list) -> list:
     # get a list of section pairs
     sections = [sections.split(",") for sections in data.split("\n")]
 
-    # generate a list of section set pairs
+    # generate a list of section pairs with sets of discrete ranges
     sets = list()
     for pair in sections:
         a, b = pair[0].split("-")