What does % mean in this statement in kotlin?

Question

I am learning kotlin and in a snipped of code iterating through a list i have this line: currentIndex = (currentIndex + 1) % myList.size

I am confused by the % sign. Does it mean that you should increment currentIndex by 1 until you get to the size of myList?

I couldnt find anything in documentation about it and the text book just seems to assume I should know!

That is a common operator in many languages. While the semantics may differ, it's commonly used for as a "modulus" or "division remainder" operator. Any decent book or tutorial or class should have taught you that. — Some programmer dude, Dec 08 '20 at 19:55
In C, the meaning of modulo is slightly ambiguous. In Java and Kotlin, it's just the remainder operator, so there's no ambiguity. — Tenfour04, Dec 08 '20 at 21:17

Arritmic · Answer 1 · 2020-12-09T02:56:42.107

1

Modulus operator. Take a look to the next links:

EDIT 1: Sorry, I forgot to answer your question really.

What it makes that statement is to increment the currentIndex by 1 at each iteration, until it ranges the whole list. When that happens, the currentIndex is initialized to 0 again. When currentIndex = 9, the next iteration will be set to zero again.

Cheers.

edited Dec 09 '20 at 02:56

answered Dec 08 '20 at 20:04

Arritmic

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thanks, i get what the modulus operator does i just dont understand why i wouldnt just do currentIndex + 1, the size of my list is 10 so 1 modulo 10 is 1 2 modulo 10 is 2 and so on, wouldnt i acheive the same result by just doing currentIndex++ – LearningToCode Dec 08 '20 at 20:52
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What would happen if `currentIndex` were 9? – Louis Wasserman Dec 08 '20 at 21:58
@LearningToCode I have edited the answer because I missed really the question. Sorry!! – Arritmic Dec 09 '20 at 02:57
ah i see that makes much more sense, thank you :) – LearningToCode Dec 09 '20 at 21:28

What does % mean in this statement in kotlin?

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