QuantumRandomNumber

from qiskit import *


def convert_to_binary(number: int) -> str:
    '''Converts a denary number to binary'''
    
    strNum = ''
    i = 0
    while True: 
        if number < 2**i:
            i -= 1
            break
        elif number == 2**i:
            break
        i += 1
    while True:
        if number >= 2**i:
            number -= 2**i
            strNum += '1'
            i -= 1
        else:
            strNum += '0'
            i -= 1
        if i == -1:
            break

    return strNum




def create_quantum_circuit(bin_upper: str) -> None:
    '''
    Creates a quantum circuit with length of upper in binary as the amount of qubits.
    Each qubit is then put in super position
    '''
    
    global qc
    qc = QuantumCircuit(len(bin_upper))

    for i in range (len(bin_upper)):
        qc.h(i)

def run_quantum_circuit() -> str:
    '''Runs the circuit with one shot and gets the result'''

    simulator = Aer.get_backend('qasm_simulator')
    qc.measure_all()
    result = execute(qc, backend = simulator, shots = 1).result()
    binary_num = str(list(result.get_counts(qc).keys())[0])
    return binary_num
    
    
    
    
def convert_to_decimal(number: str) -> int:
    '''Converts binary to decimial'''
    
    decimal = 0
    for i in range(len(number)):
        if number[-1] == '1':
    
            decimal += 2**i
        number = number[:-1]
    return decimal
    
def generate_number(lower: int, upper: int) -> int:
    '''generates the random number within the specified range'''
    
    lower, upper = [int(x) for x in input('Enter your lower bound (inclusive) then your upper bound (inclusive). In format n m: ').split()]
    
    bin_lower = convert_to_binary(lower)
    bin_upper = convert_to_binary(upper)
    create_quantum_circuit(bin_upper)
    
    number = convert_to_decimal(run_quantum_circuit())
    
    while int(number) > int(upper) or int(number) < int(lower):
        create_quantum_circuit(bin_upper)
        number = convert_to_decimal(run_quantum_circuit())
       
    print(number)
    return(number)
    
   
generate_number(lower,upper)