Thread: Return values and pointers

  1. #1
    Registered User
    Join Date
    Dec 2011

    Return values and pointers

    I am curious on how the return values work.

    I know the basics.

    int x;
    int getMyInt() {
    return x;
    void test() {
    void modify(int y) {
    y = 3;
    Can someone explain how the data flow works here?

  2. #2
    Algorithm Dissector iMalc's Avatar
    Join Date
    Dec 2005
    New Zealand
    'modify' has no effect on the variable passed into it because you are passing by value.
    To see why y is just a copy of the parameter, consider that it is perfectly okay to do:
    This clearly does not make 42 equal to 3.

    What you want is to pass by reference.
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