Getting different address every time

Question

In the following code, I get a different address every time for the first element of std::vector v. Why is it so?

#include <memory>
#include <iostream>
#include <vector>

int main()
{
    std::vector<int> v;

    for (int i=0; i<10; ++i)
    {
        int b = i;

        v.push_back(b);

        std::cout << std::addressof(v[0]) << std::endl;
    }

    return 0;
}

Output:

0x603010
0x603030
0x603010
0x603010
0x603050
0x603050
0x603050
0x603050
0x603080
0x603080

Answer 1

Because new memory may have to be allocated for the data contained in the vector when you call

 v.push_back(b);

P.S.

You said:

In the following code, I get a different address every time for the first element of std::vector v. Why is it so?

If you look at your output, that is not true for every time :)