Merged back changes from presentation

diff --cc programming.html
index 3323da422795aefe98923a9d09883cc958948fcc,2f965079bb2de400c451e5eb084890a75f8b804d..fb855a26af019ddd096bf26c6b965c082a010c21
--- 1/programming.html
--- 2/programming.html
+++ b/programming.html
@@@ -323,6 -320,14 +320,10 @@@ Do both with explicit iteration, then u
  grid_nums = [int(n) for n in GRID_STRING.split()]
  ```
  
 -
+ ---
+ 
+ # Solutions with explicit loops
 -```python
 -grid_nums = [int(n) for n in GRID_STRING.split()]
 -```
+ 
  ```python
  g1 = []
  for rowstart in range(0, ROWS * COLUMNS, COLUMNS):