mirror of
https://github.com/TheAlgorithms/Python.git
synced 2024-10-06 05:39:30 +00:00
116 lines
3.8 KiB
Python
116 lines
3.8 KiB
Python
"""
|
|
Build the quantum full adder (QFA) for any sum of
|
|
two quantum registers and one carry in. This circuit
|
|
is designed using the Qiskit framework. This
|
|
experiment run in IBM Q simulator with 1000 shots.
|
|
.
|
|
References:
|
|
https://www.quantum-inspire.com/kbase/full-adder/
|
|
"""
|
|
|
|
import math
|
|
|
|
import qiskit
|
|
|
|
|
|
def quantum_full_adder(
|
|
input_1: int = 1, input_2: int = 1, carry_in: int = 1
|
|
) -> qiskit.result.counts.Counts:
|
|
"""
|
|
# >>> q_full_adder(inp_1, inp_2, cin)
|
|
# the inputs can be 0/1 for qubits in define
|
|
# values, or can be in a superposition of both
|
|
# states with hadamard gate using the input value 2.
|
|
# result for default values: {11: 1000}
|
|
qr_0: ──■────■──────────────■──
|
|
│ ┌─┴─┐ ┌─┴─┐
|
|
qr_1: ──■──┤ X ├──■────■──┤ X ├
|
|
│ └───┘ │ ┌─┴─┐└───┘
|
|
qr_2: ──┼─────────■──┤ X ├─────
|
|
┌─┴─┐ ┌─┴─┐└───┘
|
|
qr_3: ┤ X ├─────┤ X ├──────────
|
|
└───┘ └───┘
|
|
cr: 2/═════════════════════════
|
|
Args:
|
|
input_1: input 1 for the circuit.
|
|
input_2: input 2 for the circuit.
|
|
carry_in: carry in for the circuit.
|
|
Returns:
|
|
qiskit.result.counts.Counts: sum result counts.
|
|
>>> quantum_full_adder(1, 1, 1)
|
|
{'11': 1000}
|
|
>>> quantum_full_adder(0, 0, 1)
|
|
{'01': 1000}
|
|
>>> quantum_full_adder(1, 0, 1)
|
|
{'10': 1000}
|
|
>>> quantum_full_adder(1, -4, 1)
|
|
Traceback (most recent call last):
|
|
...
|
|
ValueError: inputs must be positive.
|
|
>>> quantum_full_adder('q', 0, 1)
|
|
Traceback (most recent call last):
|
|
...
|
|
TypeError: inputs must be integers.
|
|
>>> quantum_full_adder(0.5, 0, 1)
|
|
Traceback (most recent call last):
|
|
...
|
|
ValueError: inputs must be exact integers.
|
|
>>> quantum_full_adder(0, 1, 3)
|
|
Traceback (most recent call last):
|
|
...
|
|
ValueError: inputs must be less or equal to 2.
|
|
"""
|
|
if (
|
|
isinstance(input_1, str)
|
|
or isinstance(input_2, str)
|
|
or isinstance(carry_in, str)
|
|
):
|
|
raise TypeError("inputs must be integers.")
|
|
|
|
if (input_1 < 0) or (input_2 < 0) or (carry_in < 0):
|
|
raise ValueError("inputs must be positive.")
|
|
|
|
if (
|
|
(math.floor(input_1) != input_1)
|
|
or (math.floor(input_2) != input_2)
|
|
or (math.floor(carry_in) != carry_in)
|
|
):
|
|
raise ValueError("inputs must be exact integers.")
|
|
|
|
if (input_1 > 2) or (input_2 > 2) or (carry_in > 2):
|
|
raise ValueError("inputs must be less or equal to 2.")
|
|
|
|
# build registers
|
|
qr = qiskit.QuantumRegister(4, "qr")
|
|
cr = qiskit.ClassicalRegister(2, "cr")
|
|
# list the entries
|
|
entry = [input_1, input_2, carry_in]
|
|
|
|
quantum_circuit = qiskit.QuantumCircuit(qr, cr)
|
|
|
|
for i in range(0, 3):
|
|
if entry[i] == 2:
|
|
quantum_circuit.h(i) # for hadamard entries
|
|
elif entry[i] == 1:
|
|
quantum_circuit.x(i) # for 1 entries
|
|
elif entry[i] == 0:
|
|
quantum_circuit.i(i) # for 0 entries
|
|
|
|
# build the circuit
|
|
quantum_circuit.ccx(0, 1, 3) # ccx = toffoli gate
|
|
quantum_circuit.cx(0, 1)
|
|
quantum_circuit.ccx(1, 2, 3)
|
|
quantum_circuit.cx(1, 2)
|
|
quantum_circuit.cx(0, 1)
|
|
|
|
quantum_circuit.measure([2, 3], cr) # measure the last two qbits
|
|
|
|
backend = qiskit.Aer.get_backend("aer_simulator")
|
|
job = qiskit.execute(quantum_circuit, backend, shots=1000)
|
|
|
|
return job.result().get_counts(quantum_circuit)
|
|
|
|
|
|
if __name__ == "__main__":
|
|
print(f"Total sum count for state is: {quantum_full_adder(1, 1, 1)}")
|