Array index out of range corrupts variable

#include "pch.h"
#include <iostream>

using namespace std;

int main()
{
    const int n = 10;
    int test = 2607;
    int test1 = -1;
    int a[n] = { 0 };

    cout << "&test=" << &test << " &imin=" << &test1 << endl;
    cout << "&a[0]=" << &a[0] << " &a[n-1]=" << &a[n - 1] << endl;
    cout << "&a[n-1+5]=" << &a[n - 1 + 6] << endl;
    cout << "VALUE: test=" << test << endl;
    cout << "VALUE: a[n-1+6]=" << a[n - 1 + 6] << endl;
    a[n - 1 + 6] = 3040;
    cout << "VALUE: test=" << test << endl;

}