Changed a couple of items under arrays.

plan.txt

@@ -148,7 +148,7 @@ Arrays
         - Resizing arrays:
             - https://class.coursera.org/algs4partI-010/lecture/19
             - https://www.lynda.com/Developer-Programming-Foundations-tutorials/Resizable-arrays/149042/177108-4.html
-    - Implement a vector (mutable array with automatic resizing):
+    * - Implement a vector (mutable array with automatic resizing):
         * - Practice coding using arrays and pointers, and pointer math to jump to an index instead of using indexing.
         * - new raw data array with allocated memory
             - can allocate int array under the hood, just not use its features
@@ -157,22 +157,22 @@ Arrays
         * - capacity() - number of items it can hold
         * - is_empty()
         * - at(index) - returns item at given index, blows up if index out of bounds
-        * - append(item) - or push(item) - check size of element 2^
+        * - push(item)
-        * - insert(index, item)
+        * - insert(index, item) - inserts item at index, shifts that index's value and trailing elements to the right
         * - prepend(item) - can use insert above at index 0
         * - pop() - remove from end, return value
-        - delete(index) - delete item at index, shifting all trailing elements left
+        * - delete(index) - delete item at index, shifting all trailing elements left
-        - remove(item) - looks for value and removes index holding it (even if in multiple places)
+        * - remove(item) - looks for value and removes index holding it (even if in multiple places)
-        - find(item) - looks for value and returns first index with that value
+        * - find(item) - looks for value and returns first index with that value, -1 if not found
         * - resize(new_capacity) // private function
             - when you reach capacity, resize to double the size
             - when popping an item, if size is 1/4 of capacity, resize to half
-    - Time
+    * - Time
         - O(1) to add/remove at end (amortized for allocations for more space), index, or update
         - O(n) to insert/remove elsewhere
-    - Space
+    * - Space
         - contiguous in memory, so proximity helps performance
-        - space needed = (array capacity, which is >= n) * size of item
+        - space needed = (array capacity, which is >= n) * size of item, but even if 2n, still O(n)
 Linked lists
     - singly-linked
         * - Description: https://www.coursera.org/learn/data-structures/lecture/kHhgK/singly-linked-lists
@@ -189,18 +189,20 @@ Linked lists
             - push_front
             - get_front
             - pop_front
-            - push_back
+            - insert_before(node, value)
-            - get_back
+            - insert_after(node, value)
-            - pop_back
-            - insert_before(node, item)
-            - insert_after(node, item)
             - size()
             - is_empty()
-            - find(item) - assume each item is unique
+            - find(value) - assume each item is unique
-            - remove(item) - assume each item is unique
+            - remove(value) - assume each item is unique
+            - reverse - reverses the list
     - doubly-linked list
         - Description: https://www.coursera.org/learn/data-structures/lecture/jpGKD/doubly-linked-lists
-    - reverse a singly-linked list
+        - implement:
+            - same as above for singly linked list
+            - push_back()
+            - get_back()
+            - pop_back()
 Stacks
     - see: https://class.coursera.org/algs4partI-010/lecture
     - https://www.coursera.org/learn/data-structures/lecture/UdKzQ/stacks