Quantum Out-Of-Place Addition Of A Constant

Basic math, eh?

Studying quantum computing is the best thing to do if you want to learn the basic classical algorithms, because the development of quantum circuits forces us to reimplement the fundamentals.

Quantum computing promises to solve problems that are unsolvable for classical machines. Yet, we are still working on a clear demonstration of this advantage. Before we can tackle truly "quantum-exclusive" challenges, we often have to reimplement routines that classical computers have been executing flawlessly for decades.

The out-of-place addition is one of these challenges.

It adds a fixed classical constant to a quantum register containing an unknown value and stores the result in a new register without changing the original.