import sys
import argparse
from random import randint


parser = argparse.ArgumentParser(description="Hello, please give the array of population iteams and the \
number of items to be chosen")
parser.add_argument('-l', '--list', help='Comma separated delimited list input', type=str)
parser.add_argument('number', help='The number of items to be chosen')
args = parser.parse_args()


population = [int(item) for item in args.list.split(',')]
print(population)
m = args.number


def SelectionSampling(population, m):
    m = int(m) #Is there a better way to right this?
    S = []
    k, t = 0, 0
    n = len(population)
    while k < m:
        u = randint(0, 1)
        if u * (n - t) < (m - k):
            S.append(population[t]) # List index out of range
            k += 1
        t += 1
    return S


sample = SelectionSampling(population, m)
print(sample)