This is not going to be as helpful as I would like to be but, I use flow charts as an opportunity to reinforce the thinking behind fixed loops, in that they are conditional loops, they just have a predefined limited condition. There is a counter involved it’s just that is it hidden from the student.
I find this useful because it reminds them why, in python for instance, you can iterate through a list using the fixed loops counter as the index position.
As I said, maybe not as helpful as you wanted but I always include a loop counter when flow charting a fixed loop.
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