Deutsch–Jozsa algorithm

Deutsch–Jozsa.py

from matplotlib import pyplot as plt
import numpy as np
from qiskit import *

# Creating a circuit with 3 quantum bits and 2 classical bit
qc = QuantumCircuit(3,2)

# Preparing inputs
qc.h(0)
qc.h(1)
qc.x(2)
qc.h(2)

qc.barrier()

# Oracle function
qc.cx(0,2)
qc.cx(1,2)

qc.barrier()

# Preparing output
qc.h(0)
qc.h(1)

qc.barrier()

# measuring the results
qc.measure(0,0)
qc.measure(1,1)

qc.draw(output='mpl')

# Running the experiment in simulator
simulator = Aer.get_backend('qasm_simulator')
result = execute(qc,backend=simulator,shots=1024).result()
plot_histogram(result.get_counts())

# Running the experiment in actual IBM quantum computer
IBMQ.load_account()
job = execute(qc,IBMQ.get_provider('ibm-q').get_backend('ibmq_16_melbourne'))

# Job status = queued -> finished
job_monitor(job)

plot_histogram(job.result().get_counts())