Why does this program print 13 instead of 15?

Asked Feb 08 '21 at 07:19

Active Feb 08 '21 at 07:19

Viewed 30 times

public static void main(String[] args) {
    int number = 3;
    modifyNumber(number);
    System.out.println(addAndReturn(number));
}

public static void modifyNumber(int number) {
    number = number + 2;
}

public static int addAndReturn(int number) {
    return number + 10;
}

I reviewed the code many times but i still don't understand it. The method "modifyNumber" doesn´t create a variable inside itself so, shouldn't it actually modify the main method's number variable?

asked Feb 08 '21 at 07:19

Because `modifyNumber` doesn't modidy `number`. – Federico klez Culloca Feb 08 '21 at 07:20
Better explained, because it modifies the local variable number in the modifyNumber method, but that doesn't alter the number variable in your main method – Stultuske Feb 08 '21 at 07:22
What you tried is value by reference which is more a C/C++ style. You shoud you a class member variable or return the value of `number`. – FaltFe Feb 08 '21 at 07:22

Why does this program print 13 instead of 15?

0 Answers0