If you find any problems with my methodology and/or results, please let me know and I will update the article. Hopefully, this rumination on for-loops was illuminating - it’s as exciting as I could make it. Practical differences in efficiency are minimal but may be enough to sway you one way or another if you were looking for any difference at all.Both are identical when used on arrays, lists and other iterables.In which case you want to check the grade and then increment the numOfX value by 1. If I read the prompt correctly, you want to know how many students got each grade. So for a: a5+5 numOfA10/5 > 2 The rest are similar. which is complemented by in and in.Range is defined for. You are adding to a each time and then dividing by the letter grade. Learn Kotlin - Range expressions are formed with rangeTo functions that have the operator form. Functional forEach allocates one or two more objects on numeric ranges (depending on the conditions) but somewhat more consistent, especially when used around other functional operations (e.g. It looks like the logic in the loop is wrong.Traditional for-loops are slightly more memory efficient on numeric ranges and probably more readable for Java developers, albeit less “functional”.The same would apply to all other implementations of Iterable, including built-in types and anything custom you may conjure. In Kotlin, we have one universal for-loop that can be expressively used to iterate over a collection, a map, a range of numbers, and much more. Traditional for-loop: for (i in 0.10).

Let’s say you want to loop over a range of integers, you have two options:

Kotlin for loop range