Coding Deutsch’s algorithm

Most of the code in this section uses Qiskit features from previous chapters.

First, we have our import declarations:

from qiskit import QuantumCircuit, executefrom qiskit_ibm_provider import IBMProvider
from enum import Enum

To distinguish between the simple binary functions, we create a Python enumeration:

class SimpleBinary(Enum):    ZERO        = 0
    ONE         = 1
    SAME_AS     = 2
    OPPOSITE_OF = 3

This chapter’s code makes little use of the SimpleBinary enumeration. But having an enumeration feels better than just assigning the numbers 0, 1, 2, and 3 to the four functions.

Our get_oracle code adds different gates to a circuit depending on which of the simple binary functions we want to implement:

def get_oracle(circ, function...