How to see that both are adder circuits in terms of conventional classical circuit logic ?

Strange, the first circuit uses QFT , while the second circuit is using ripple-carry architecture



1 Answer 1


The first one uses Fourier basis to represent numbers, so that addition and subtraction can just be translated into rotations of respectively sized angles. Look at Qiskit Quantum Fourier Transform tutorial, it gives an intuitive view on the number representations.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.