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Old June 8th, 2003, 11:18 PM
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Default Pointers and Arrays C++

In this little program I enter 10 integers and display them back
using arithmetical operation to a pointer.
it compiles, accepts my input, display the elements, but right after
that it causes an error. if I delete the "delete [] numbers" I will
be OK and if I use the pointer notation syntax "*(numbers + i)"
it works fine. here's the code...
can anyone explain me why? TIA

#include <iostream>

using namespace std;

int main ()
    const int max_value = 10;
    int* numbers = new int[max_value];
    int cnt = 0;

        cout << "\nPlease, enter integer #" << cnt + 1 << ": ";
        cin >> *(numbers + cnt);
    }while (cnt < 10);

    for (int i = 0; i < max_value; i++, numbers++)
        cout << endl << *numbers << endl;

    delete [] numbers;

    cout << endl;
    return 0;
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Old July 10th, 2003, 01:45 PM
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The reason is because your pointer variable is no longer pointing at the memory location you initialized using new.

In your for loop you are incremementing the location pointed to by the numbers variable. At the end of the loop numbers is pointing at a different location than where it started.

For this particular example to work I would add the following line of code at right after the for loop.

numbers -= max_value;

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