How to hack a system with c++

Answer 1

I don't know... but make sure you go white-hat (eg, break into your own computer), since it would be illegal otherwise, and the penalties are pretty stiff.
By the way, macros (eg, microsoft office) might be easier to use to hack with.

Answer 2

use the code:-
while(true)
cout<<"Do Something PC. Hack it."

Trust me it will work.