Something

#include<iostream>
int main() {
    int *i = new int;
    *i = 42;
    int *bla = new int[10];
    std::cout << "i: "  << *i << " mit adresse: " << i << std::endl;
    std::cout << "bla[-sizeof(int)]: " << bla[-sizeof(int)] << " mit adresse: " << (bla-sizeof(int)) << std::endl;
}