Value referenced by pointer changes when passing from function [duplicate]

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• Can a local variable's memory be accessed outside its scope? 18 answers

I am trying to pass an array out of a function using pointers. When I dereference the pointer inside the function, it gives the correct value, but when it is dereferenced in the main function, it gives a wildly different value.

#include <iostream>

using namespace std;

int* func()  {
    int arr[4] = {0,1,2,3};
    int* ptr = arr;
    cout << ptr << endl;
    cout << *ptr << endl;
    return ptr;
}

int main()
{
    int* ptr;
    ptr = func();
    cout << ptr << endl;
    cout << *ptr << endl;

    return 0;
}