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Thread: Decrement operator help.

  1. September 17th, 2020, 12:42 AM #1
    Independent_Learner
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    Default Decrement operator help. 

    public class Main {
public static void main(String[] args){
 
	int a = 10;
	int b = (--a + 2)*3;
	System.out.println(a);
	System.out.println(b);
 
	}
}
    System.out.println(b) outputs 33 instead of 36. Could someone please explain this to me. Thanks.
    Last edited by Norm; September 17th, 2020 at 05:18 AM. Reason: Added ending code tag
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  2. September 17th, 2020, 05:20 AM #2
    Norm
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    Default Re: Decrement operator help.

    Why do you expect 36? (9+2)*3 = 33
    If you don't understand my answer, don't ignore it, ask a question.
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  3. September 17th, 2020, 06:39 AM #3
    arhzz
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    Default Re: Decrement operator help.

    Okay I'm not quite sure why you are expecting 36 but I'll try to go step by step so you understand why its 33.


    int b = (--a + 2) * 3

    so considering a is 10, we have ( --10 + 2 ) * 3. The -- 10 part means its an PRE-decrement meaning that variable will be decreased by 1 before the other operations so than it becomes (9 + 2) * 3, brackets have "higher priority" than multiplication so its 11 * 3 = 33.

    Hope this help!
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