diff --git a/README.md b/README.md
index 40ead10..2d7d9f0 100644
--- a/README.md
+++ b/README.md
@@ -182,9 +182,13 @@ Exercises Needed: 13, 15, 17, 19, 21, 23, 25, 27, 29, 31
Chapter 20
- - Lists, Stacks, Queues, and Priority Queues
+ - Lists, Stacks, Queues, and Priority Queues
+
+
Chapter 21
- - Sets and Maps
+ - Sets and Maps
+
+
Chapter 22
- Developing Efficient Algorithms
Chapter 23