Good you have a print at the start of the loop.
I would also add more prints in the if and else branches as well as at the end of the loop. Then you will know a lot more about how you changed start, middle and end.
Good you have a print at the start of the loop.
I would also add more prints in the if and else branches as well as at the end of the loop. Then you will know a lot more about how you changed start, middle and end.