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function - Returning a pointer of a local variable C++

I need to create a function that returns a pointer to an int.

Like so:

int * count()
{
    int myInt = 5;

    int * const p = &myInt;

    return p;
}

Since a pointer is simply an address, and the variable myInt is destroyed after this function is called. How do I declare an int inside this method that will keep a place in the memory in order for me to access it later via the returned pointer? I know I could declare the int globally outside of the function, but I want to declare it inside the function.

Thanks in advance for any help!

Question&Answers:os

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1 Answer

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by (71.8m points)

Use the new operator

int * count()
{
    int myInt = 5;

    int * p = new int;
    *p = myInt;

    return p;
}

As pointed out in other answers this is generally a bad idea. If you must do it this way then maybe you can use a smart pointer. See this question for how to do this What is a smart pointer and when should I use one?


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