From 1d22356ce52fc385f4fce906056017fd5e6e3257 Mon Sep 17 00:00:00 2001
From: onyx-and-iris <code@onyxandiris.online>
Date: Tue, 6 Feb 2024 22:04:37 +0000
Subject: [PATCH] upd readmes, rename exercises.

---
 chapter3/README.md                  | 10 ++++++++++
 chapter4/README.md                  | 11 ++++-------
 chapter4/{summation.py => ex4.1.py} |  0
 chapter4/{maximum.py => ex4.3.py}   |  0
 chapter4/{binary.py => ex4.4.py}    |  0
 5 files changed, 14 insertions(+), 7 deletions(-)
 create mode 100644 chapter3/README.md
 rename chapter4/{summation.py => ex4.1.py} (100%)
 rename chapter4/{maximum.py => ex4.3.py} (100%)
 rename chapter4/{binary.py => ex4.4.py} (100%)

diff --git a/chapter3/README.md b/chapter3/README.md
new file mode 100644
index 0000000..efed166
--- /dev/null
+++ b/chapter3/README.md
@@ -0,0 +1,10 @@
+# Recursion
+
+Recursive functions must have both:
+
+-   one or more base cases
+-   a recursive case
+
+The base cases are required to ensure the recursion stops when meeting a condition
+
+The recursive case adds functions onto the call stack and completes each one top down.
diff --git a/chapter4/README.md b/chapter4/README.md
index 37fffe3..dca162d 100644
--- a/chapter4/README.md
+++ b/chapter4/README.md
@@ -1,12 +1,9 @@
-# Recursion
+# Quicksort
 
-Recursive functions must have both:
+Similar to the previous recursive function, quicksort uses divide and conquer.
 
--   one or more base cases
--   a recursive case
+The base case occurs for an array size 0 or 1 (doesn't need to be sorted).
 
-The base cases are required to ensure the recursion stops when meeting a condition
-
-The recursive case adds functions onto the call stack and completes each one top down.
+The recursive case works by partitioning the array around a chosen pivot repeatedly until the base case is met and then combining all sorted sub-arrays.
 
 Note. Quicksort should be implemented using a random pivot to ensure average runtimes.
diff --git a/chapter4/summation.py b/chapter4/ex4.1.py
similarity index 100%
rename from chapter4/summation.py
rename to chapter4/ex4.1.py
diff --git a/chapter4/maximum.py b/chapter4/ex4.3.py
similarity index 100%
rename from chapter4/maximum.py
rename to chapter4/ex4.3.py
diff --git a/chapter4/binary.py b/chapter4/ex4.4.py
similarity index 100%
rename from chapter4/binary.py
rename to chapter4/ex4.4.py