Reorganized sorting section. Moved some lectures to additional section.

README.md

@@ -733,8 +733,7 @@ Write code on a whiteboard or paper, not a computer. Test with some sample input
             the Completely Fair Scheduler used in current Linux kernels uses red–black trees. In the version 8 of Java,
             the Collection HashMap has been modified such that instead of using a LinkedList to store identical elements with poor
             hashcodes, a Red-Black tree is used.
-        - [ ] [Aduni - Algorithms - Lecture 4
-            (link jumps to starting point) (video)](https://youtu.be/1W3x0f_RmUo?list=PLFDnELG9dpVxQCxuD-9BSy2E7BWY3t5Sm&t=3871)
+        - [ ] [Aduni - Algorithms - Lecture 4 (link jumps to starting point) (video)](https://youtu.be/1W3x0f_RmUo?list=PLFDnELG9dpVxQCxuD-9BSy2E7BWY3t5Sm&t=3871)
         - [ ] [Aduni - Algorithms - Lecture 5 (video)](https://www.youtube.com/watch?v=hm2GHwyKF1o&list=PLFDnELG9dpVxQCxuD-9BSy2E7BWY3t5Sm&index=5)
         - [ ] [Black Tree](https://en.wikipedia.org/wiki/Red%E2%80%93black_tree)
         - [ ] [An Introduction To Binary Search And Red Black Tree](https://www.topcoder.com/community/data-science/data-science-tutorials/an-introduction-to-binary-search-and-red-black-trees/)
@@ -761,27 +760,18 @@ Write code on a whiteboard or paper, not a computer. Test with some sample input
 
 - For heapsort, see Heap data structure above. Heap sort is great, but not stable.
 
-- [ ] [Bubble Sort (video)](https://www.youtube.com/watch?v=P00xJgWzz2c&index=1&list=PL89B61F78B552C1AB)
-- [ ] [Analyzing Bubble Sort (video)](https://www.youtube.com/watch?v=ni_zk257Nqo&index=7&list=PL89B61F78B552C1AB)
-- [ ] [Insertion Sort, Merge Sort (video)](https://www.youtube.com/watch?v=Kg4bqzAqRBM&index=3&list=PLUl4u3cNGP61Oq3tWYp6V_F-5jb5L2iHb)
-- [ ] [Insertion Sort (video)](https://www.youtube.com/watch?v=c4BRHC7kTaQ&index=2&list=PL89B61F78B552C1AB)
-- [ ] [Merge Sort (video)](https://www.youtube.com/watch?v=GCae1WNvnZM&index=3&list=PL89B61F78B552C1AB)
-- [ ] [Quicksort (video)](https://www.youtube.com/watch?v=y_G9BkAm6B8&index=4&list=PL89B61F78B552C1AB)
-- [ ] [Selection Sort (video)](https://www.youtube.com/watch?v=6nDMgr0-Yyo&index=8&list=PL89B61F78B552C1AB)
-
-- [ ] Stanford lectures on sorting:
-    - [ ] [Lecture 15 | Programming Abstractions (video)](https://www.youtube.com/watch?v=ENp00xylP7c&index=15&list=PLFE6E58F856038C69)
-    - [ ] [Lecture 16 | Programming Abstractions (video)](https://www.youtube.com/watch?v=y4M9IVgrVKo&index=16&list=PLFE6E58F856038C69)
+- [ ] [Sedgewick - Mergesort (5 videos)](https://www.youtube.com/watch?v=4nKwesx_c8E&list=PLe-ggMe31CTeunC6GZHFBmQx7EKtjbGf9)
+    - [ ] [1. Mergesort](https://www.youtube.com/watch?v=4nKwesx_c8E&list=PLe-ggMe31CTeunC6GZHFBmQx7EKtjbGf9&index=1)
+    - [ ] [2. Bottom up Mergesort](https://www.youtube.com/watch?v=HGOIGUYjeyk&list=PLe-ggMe31CTeunC6GZHFBmQx7EKtjbGf9&index=2)
+    - [ ] [3. Sorting Complexity](https://www.youtube.com/watch?v=WvU_mIWo0Ac&index=3&list=PLe-ggMe31CTeunC6GZHFBmQx7EKtjbGf9)
+    - [ ] [4. Comparators](https://www.youtube.com/watch?v=7MvC1kmBza0&index=4&list=PLe-ggMe31CTeunC6GZHFBmQx7EKtjbGf9)
+    - [ ] [5. Stability](https://www.youtube.com/watch?v=XD_5iINB5GI&index=5&list=PLe-ggMe31CTeunC6GZHFBmQx7EKtjbGf9)
 
-- [ ] Shai Simonson, [Aduni.org](http://www.aduni.org/):
-    - [ ] [Algorithms - Sorting - Lecture 2 (video)](https://www.youtube.com/watch?v=odNJmw5TOEE&list=PLFDnELG9dpVxQCxuD-9BSy2E7BWY3t5Sm&index=2)
-    - [ ] [Algorithms - Sorting II - Lecture 3 (video)](https://www.youtube.com/watch?v=hj8YKFTFKEE&list=PLFDnELG9dpVxQCxuD-9BSy2E7BWY3t5Sm&index=3)
-
-- [ ] Steven Skiena lectures on sorting:
-    - [ ] [lecture begins at 26:46 (video)](https://youtu.be/ute-pmMkyuk?list=PLOtl7M3yp-DV69F32zdK7YJcNXpTunF2b&t=1600)
-    - [ ] [lecture begins at 27:40 (video)](https://www.youtube.com/watch?v=yLvp-pB8mak&index=8&list=PLOtl7M3yp-DV69F32zdK7YJcNXpTunF2b)
-    - [ ] [lecture begins at 35:00 (video)](https://www.youtube.com/watch?v=q7K9otnzlfE&index=9&list=PLOtl7M3yp-DV69F32zdK7YJcNXpTunF2b)
-    - [ ] [lecture begins at 23:50 (video)](https://www.youtube.com/watch?v=TvqIGu9Iupw&list=PLOtl7M3yp-DV69F32zdK7YJcNXpTunF2b&index=10)
+- [ ] [Sedgewick - Quicksort (4 videos)](https://www.youtube.com/playlist?list=PLe-ggMe31CTeE3x2-nF1-toca1QpuXwE1)
+    - [ ] [1. Quicksort](https://www.youtube.com/watch?v=5M5A7qPWk84&index=1&list=PLe-ggMe31CTeE3x2-nF1-toca1QpuXwE1)
+    - [ ] [2. Selection](https://www.youtube.com/watch?v=CgVYfSyct_M&index=2&list=PLe-ggMe31CTeE3x2-nF1-toca1QpuXwE1)
+    - [ ] [3. Duplicate Keys](https://www.youtube.com/watch?v=WBFzOYJ5ybM&index=3&list=PLe-ggMe31CTeE3x2-nF1-toca1QpuXwE1)
+    - [ ] [4. System Sorts](https://www.youtube.com/watch?v=rejpZ2htBjE&index=4&list=PLe-ggMe31CTeE3x2-nF1-toca1QpuXwE1)
 
 - [ ] UC Berkeley:
     - [ ] [CS 61B Lecture 29: Sorting I (video)](https://www.youtube.com/watch?v=EiUvYS2DT6I&list=PL4BBB74C7D2A1049C&index=29)
@@ -789,12 +779,22 @@ Write code on a whiteboard or paper, not a computer. Test with some sample input
     - [ ] [CS 61B Lecture 32: Sorting III (video)](https://www.youtube.com/watch?v=Y6LOLpxg6Dc&index=32&list=PL4BBB74C7D2A1049C)
     - [ ] [CS 61B Lecture 33: Sorting V (video)](https://www.youtube.com/watch?v=qNMQ4ly43p4&index=33&list=PL4BBB74C7D2A1049C)
 
-- [ ] - Merge sort code:
-    - [ ] [Using output array](http://www.cs.yale.edu/homes/aspnes/classes/223/examples/sorting/mergesort.c)
-    - [ ] [In-place](https://github.com/jwasham/practice-cpp/blob/master/merge_sort/merge_sort.cc)
-- [ ] - Quick sort code:
-    - [ ] [Implementation](http://www.cs.yale.edu/homes/aspnes/classes/223/examples/randomization/quick.c)
-    - [ ] [Implementation](https://github.com/jwasham/practice-c/blob/master/quick_sort/quick_sort.c)
+- [ ] [Bubble Sort (video)](https://www.youtube.com/watch?v=P00xJgWzz2c&index=1&list=PL89B61F78B552C1AB)
+- [ ] [Analyzing Bubble Sort (video)](https://www.youtube.com/watch?v=ni_zk257Nqo&index=7&list=PL89B61F78B552C1AB)
+- [ ] [Insertion Sort, Merge Sort (video)](https://www.youtube.com/watch?v=Kg4bqzAqRBM&index=3&list=PLUl4u3cNGP61Oq3tWYp6V_F-5jb5L2iHb)
+- [ ] [Insertion Sort (video)](https://www.youtube.com/watch?v=c4BRHC7kTaQ&index=2&list=PL89B61F78B552C1AB)
+- [ ] [Merge Sort (video)](https://www.youtube.com/watch?v=GCae1WNvnZM&index=3&list=PL89B61F78B552C1AB)
+- [ ] [Quicksort (video)](https://www.youtube.com/watch?v=y_G9BkAm6B8&index=4&list=PL89B61F78B552C1AB)
+- [ ] [Selection Sort (video)](https://www.youtube.com/watch?v=6nDMgr0-Yyo&index=8&list=PL89B61F78B552C1AB)
+
+- [ ] Merge sort code:
+    - [ ] [Using output array (C)](http://www.cs.yale.edu/homes/aspnes/classes/223/examples/sorting/mergesort.c)
+    - [ ] [Using output array (Python)](https://github.com/jwasham/practice-python/blob/master/merge_sort/merge_sort.py)
+    - [ ] [In-place (C++)](https://github.com/jwasham/practice-cpp/blob/master/merge_sort/merge_sort.cc)
+- [ ] Quick sort code:
+    - [ ] [Implementation (C)](http://www.cs.yale.edu/homes/aspnes/classes/223/examples/randomization/quick.c)
+    - [ ] [Implementation (C)](https://github.com/jwasham/practice-c/blob/master/quick_sort/quick_sort.c)
+    - [ ] [Implementation (Python)](https://github.com/jwasham/practice-python/blob/master/quick_sort/quick_sort.py)
 
 - [ ] Implement:
     - [ ] Mergesort: O(n log n) average and worst case
@@ -809,6 +809,8 @@ Write code on a whiteboard or paper, not a computer. Test with some sample input
     - [ ] [Randomization: Matrix Multiply, Quicksort, Freivalds' algorithm (video)](https://www.youtube.com/watch?v=cNB2lADK3_s&index=8&list=PLUl4u3cNGP6317WaSNfmCvGym2ucw3oGp)
     - [ ] [Sorting in Linear Time (video)](https://www.youtube.com/watch?v=pOKy3RZbSws&list=PLUl4u3cNGP61hsJNdULdudlRL493b-XZf&index=14)
 
+If you need more detail on this subject, see "Sorting" section in [Additional Detail on Some Subjects](#additional-detail-on-some-subjects)
+
 ## Graphs
 
 Graphs can be used to represent many problems in computer science, so this section is long, like trees and sorting were.
@@ -1193,7 +1195,7 @@ You'll get more graph practice in Skiena's book (see Books section below) and th
         - [ ] [5. Rabin-Karp](https://www.youtube.com/watch?v=QzI0p6zDjK4&index=1&list=PLe-ggMe31CTdAdjXB3lIuf2maubzo9t66)
     - [ ] [Search pattern in text (video)](https://www.coursera.org/learn/data-structures/lecture/tAfHI/search-pattern-in-text)
     
-    If you need more detail  on this subject, see "String Matching" section in [Additional Detail on Some Subjects](#additional-detail-on-some-subjects)
+    If you need more detail on this subject, see "String Matching" section in [Additional Detail on Some Subjects](#additional-detail-on-some-subjects)
 
 ---
 
@@ -1800,6 +1802,20 @@ You're never really done.
         - nice explanation of tries
         - can be skipped
 
+- [ ] **Sorting**
+
+    - [ ] Stanford lectures on sorting:
+        - [ ] [Lecture 15 | Programming Abstractions (video)](https://www.youtube.com/watch?v=ENp00xylP7c&index=15&list=PLFE6E58F856038C69)
+        - [ ] [Lecture 16 | Programming Abstractions (video)](https://www.youtube.com/watch?v=y4M9IVgrVKo&index=16&list=PLFE6E58F856038C69)
+    - [ ] Shai Simonson, [Aduni.org](http://www.aduni.org/):
+        - [ ] [Algorithms - Sorting - Lecture 2 (video)](https://www.youtube.com/watch?v=odNJmw5TOEE&list=PLFDnELG9dpVxQCxuD-9BSy2E7BWY3t5Sm&index=2)
+        - [ ] [Algorithms - Sorting II - Lecture 3 (video)](https://www.youtube.com/watch?v=hj8YKFTFKEE&list=PLFDnELG9dpVxQCxuD-9BSy2E7BWY3t5Sm&index=3)
+    - [ ] Steven Skiena lectures on sorting:
+        - [ ] [lecture begins at 26:46 (video)](https://youtu.be/ute-pmMkyuk?list=PLOtl7M3yp-DV69F32zdK7YJcNXpTunF2b&t=1600)
+        - [ ] [lecture begins at 27:40 (video)](https://www.youtube.com/watch?v=yLvp-pB8mak&index=8&list=PLOtl7M3yp-DV69F32zdK7YJcNXpTunF2b)
+        - [ ] [lecture begins at 35:00 (video)](https://www.youtube.com/watch?v=q7K9otnzlfE&index=9&list=PLOtl7M3yp-DV69F32zdK7YJcNXpTunF2b)
+        - [ ] [lecture begins at 23:50 (video)](https://www.youtube.com/watch?v=TvqIGu9Iupw&list=PLOtl7M3yp-DV69F32zdK7YJcNXpTunF2b&index=10)
+
 ## Video Series
 
 Sit back and enjoy. "netflix and skill" :P