Trace Array Elements Through a Pointer

1#include <iostream>
2 
3int main() {
4    double values[] = {1.5, 2.5, 3.5, 4.5};
5    double* p = &values[1];
6    std::cout << p[0] << " " << p[-1] << " " << *p << "\n";
7    ++p;
8    std::cout << p[0] << " " << p[-1] << " " << *p << "\n";
9    p[0] = 10.5;
10    *(p - 1) = 20.5;
11    for (double v : values) {
12        std::cout << v << "\n";
13    }
14    return 0;
15}