Add TODO checkboxes to Python/C++ sub-headings

- roadmap.org: *** TODO Python and *** TODO C++ with [/] cookie
  on each problem heading for [0/2] progress tracking
- Note files now have TODO Approach, TODO Python, TODO C++
  sections for structured problem solving

org/cpp/dsa/arrays-hashing/0001-two-sum.org

@@ -3,6 +3,15 @@
 :NEETCODE: [[../../../../leetcode/out/roadmap.org::*0001. Two Sum][Roadmap]]
 :END:
 
+** TODO Approach
+Write your approach here.
+
+** TODO Python
+#+begin_src python
+
+#+end_src
+
+** TODO C++
 #+begin_src cpp
 
 #+end_src

org/cpp/dsa/arrays-hashing/0036-valid-sudoku.org

@@ -3,6 +3,15 @@
 :NEETCODE: [[../../../../leetcode/out/roadmap.org::*0036. Valid Sudoku][Roadmap]]
 :END:
 
+** TODO Approach
+Write your approach here.
+
+** TODO Python
+#+begin_src python
+
+#+end_src
+
+** TODO C++
 #+begin_src cpp
 
 #+end_src

org/cpp/dsa/arrays-hashing/0049-group-anagrams.org

@@ -3,6 +3,15 @@
 :NEETCODE: [[../../../../leetcode/out/roadmap.org::*0049. Group Anagrams][Roadmap]]
 :END:
 
+** TODO Approach
+Write your approach here.
+
+** TODO Python
+#+begin_src python
+
+#+end_src
+
+** TODO C++
 #+begin_src cpp
 
 #+end_src

org/cpp/dsa/arrays-hashing/0128-longest-consecutive-sequence.org

@@ -3,6 +3,15 @@
 :NEETCODE: [[../../../../leetcode/out/roadmap.org::*0128. Longest Consecutive Sequence][Roadmap]]
 :END:
 
+** TODO Approach
+Write your approach here.
+
+** TODO Python
+#+begin_src python
+
+#+end_src
+
+** TODO C++
 #+begin_src cpp
 
 #+end_src

org/cpp/dsa/arrays-hashing/0217-contains-duplicate.org

@@ -3,6 +3,15 @@
 :NEETCODE: [[../../../../leetcode/out/roadmap.org::*0217. Contains Duplicate][Roadmap]]
 :END:
 
+** TODO Approach
+Write your approach here.
+
+** TODO Python
+#+begin_src python
+
+#+end_src
+
+** TODO C++
 #+begin_src cpp
 
 #+end_src

org/cpp/dsa/arrays-hashing/0238-product-of-array-except-self.org

@@ -3,6 +3,15 @@
 :NEETCODE: [[../../../../leetcode/out/roadmap.org::*0238. Product of Array Except Self][Roadmap]]
 :END:
 
+** TODO Approach
+Write your approach here.
+
+** TODO Python
+#+begin_src python
+
+#+end_src
+
+** TODO C++
 #+begin_src cpp
 
 #+end_src

org/cpp/dsa/arrays-hashing/0242-valid-anagram.org

@@ -3,6 +3,15 @@
 :NEETCODE: [[../../../../leetcode/out/roadmap.org::*0242. Valid Anagram][Roadmap]]
 :END:
 
+** TODO Approach
+Write your approach here.
+
+** TODO Python
+#+begin_src python
+
+#+end_src
+
+** TODO C++
 #+begin_src cpp
 
 #+end_src

org/cpp/dsa/arrays-hashing/0271-encode-and-decode-strings.org

@@ -3,6 +3,15 @@
 :NEETCODE: [[../../../../leetcode/out/roadmap.org::*0271. Encode and Decode Strings][Roadmap]]
 :END:
 
+** TODO Approach
+Write your approach here.
+
+** TODO Python
+#+begin_src python
+
+#+end_src
+
+** TODO C++
 #+begin_src cpp
 
 #+end_src

org/cpp/dsa/arrays-hashing/0347-top-k-frequent-elements.org

@@ -3,6 +3,15 @@
 :NEETCODE: [[../../../../leetcode/out/roadmap.org::*0347. Top K Frequent Elements][Roadmap]]
 :END:
 
+** TODO Approach
+Write your approach here.
+
+** TODO Python
+#+begin_src python
+
+#+end_src
+
+** TODO C++
 #+begin_src cpp
 
 #+end_src

org/cpp/dsa/arrays-hashing/1408-string-matching-in-an-array.org

@@ -3,6 +3,15 @@
 :NEETCODE: [[../../../../leetcode/out/roadmap.org::*1408. String Matching in an Array][Roadmap]]
 :END:
 
+** TODO Approach
+Write your approach here.
+
+** TODO Python
+#+begin_src python
+
+#+end_src
+
+** TODO C++
 #+begin_src cpp
 
 #+end_src

org/cpp/dsa/arrays-hashing/1769-minimum-number-of-operations-to-move-all-balls-to-each-box.org

@@ -3,6 +3,15 @@
 :NEETCODE: [[../../../../leetcode/out/roadmap.org::*1769. Minimum Number of Operations to Move All Balls to Each Box][Roadmap]]
 :END:
 
+** TODO Approach
+Write your approach here.
+
+** TODO Python
+#+begin_src python
+
+#+end_src
+
+** TODO C++
 #+begin_src cpp
 
 #+end_src

org/cpp/dsa/arrays-hashing/2678-number-of-senior-citizens.org

@@ -3,6 +3,15 @@
 :NEETCODE: [[../../../../leetcode/out/roadmap.org::*2678. Number of Senior Citizens][Roadmap]]
 :END:
 
+** TODO Approach
+Write your approach here.
+
+** TODO Python
+#+begin_src python
+
+#+end_src
+
+** TODO C++
 #+begin_src cpp
 
 #+end_src